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INTERVNE.NTA
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WHEN THE OPPONENTS INTERVENE
When an Opponent Makes a Natural Overcall
This includes a natural overcall that shows in addition another
unspecified suit. If the natural overcall shows another specific
suit, the defense is different. See chapter DEFENSE VS TWO-SUITED
CONVENTIONS in the book "Marvin's Conventions and Treatments."
-- An immediate double is for business if negative doubles
(described later) are not being used.
South West North
1NT 2H Dbl - business double
-- A direct double by opener is also for business:
South West North East
1NT Pass Pass 2H
Dbl - business double, good hearts
-- A reopening double is takeout by opener, business by responder:
South West North East
1NT 2H Pass Pass
Dbl - takeout
South West North East
1NT Pass Pass 2C
Pass Pass Dbl - business double
All other doubles by either partner are for business.
-- A 4C response is always Gerber:
South West North
1NT 3C/3D 4C - Gerber
-- Jacoby transfer bids do not apply, but Texas transfers apply
after an overcall of 3C or lower (i.e., when both 4D and 4H would
be a jump):
South West North
1NT 2C 2D/2H/2S - natural
4D/4H - Texas transfer
4C - Gerber
South West North
1NT 3D 4H/4S - natural
4D - Stayman, ostensibly
South West North
1NT 2D 4D - Texas transfer
-- The cue bid replaces Stayman, and is forcing to game:
South West North
1NT 2C 3C - asks for a major
1NT 2D 3D - asks for a major
1NT 2H 3H - asks for spades
1NT 2S 3S - asks for hearts
In the first auction opener bids 3D with neither major, 3NT with
both and a minimum, 4C with both and a maximum. In the second
auction opener bids 3NT with neither major, 4D with both. (Remember
that 3C is a natural bid unless the overcall was in clubs.) The cue
bid may not be meant as Stayman when responder has a big hand with
first round control of the opposing suit. If that is so, she will
make it clear in the later bidding:
South West North East
1NT 2C 3C Pass
3H Pass 3S Pass
3NT Pass 4S - slam try, club void or ace
Obviously North was not bidding 3C to find a major suit fit.
-- Simple free bids are not forcing, and are not even invitational
at match point scoring. With an invitational hand responder must
generally bid 2NT at match points, even with a suit-oriented hand.
If space permits a jump, however, the invitation can be made that
way (but major suit jumps are forcing at IMP scoring):
South West North
1NT 2C 3D/3H/3S - invitational
When the overcall is at the three level, a 3H or 3S response is
invitational at IMP scoring but not at match points. A 4C response
is always Gerber. Over 3C, a 3D response is used for Stayman (but
is natural, weak, if a double is negative).
South West North
1NT 3C 3D - Stayman or natural
3H/3S - not forcing
4C - Gerber
4D/4H - Texas Transfer
If the overcall is 3D or higher, Texas does not apply, and a cue
bid must be used for Stayman unless negative doubles apply.
When responder raises to 2NT over an overcall, opener should show
a major on his way to 3NT. A new minor suit rebid shows a maximum
hand, five-card suit, and no stopper in the opposing suit.
An optional strategy against two-level overcalls is Rumpelsohl:
Rumpelsohl
Rumpelsohl is a variation of Lebensohl, which uses a 2NT response
to 1NT in competition as an artificial bid asking opener to bid 3C,
after which responder can pass or bid. Incorporating transfers
enables responder to show three types of hand containing a long
suit: weak, invitational, or forcing. Responder can also show two
suits via Rumpelsohl. The author of Rumpelsohl is Paul van
Rijckevorsel of the Netherlands (Bridge World, October 1992). The
version given here is an extension of the original version.
Rumpelsohl may be applied selectively, as against non-vulnerable
opponents only, or only with unfavorable vulnerability. When using
Rumpelsohl, you should also use negative doubles (described below).
Since you are unable to make a natural raise to 2NT, you need
another way of possibly getting into the action with an invita-
tional hand that lacks a long suit. Negative doubles may permit a
bad overcall to go unpunished, which is why vulnerability may be
a factor.
Rumpelsohl applies only over natural overcalls that show the suit
bid (even if the overcall shows in addition another, unspecified,
suit--perhaps identified as a major, or minor, or pointed suit, or
rounded suit, but not specifically identified). If the overcall
shows two specific suits, use the countermeasures described in
chapter DEFENSE VS TWO-SUITED CONVENTIONS in the book "Marvin's
Conventions and Treatments."
Here's how (my version of) Rumpelsohl works:
A free 2NT response shows either invitational strength or a club
bust. Partner must bid 3C, after which responder can pass or make
his invitational bid (no transfers here):
South West North East
1NT 2S 2NT Pass
3C Pass Pass - club bust
3D/3H/3S/4C - invitational
3NT - clubs, invitational
The Rumpelsohl bidder bids 4C to invite a club game with a hand
that is unsuitable for notrump, 3NT with one that is suitable. To
bid 3NT he either has spades stopped or a fairly solid suit (not
both, which would be too much strength for a Rumpelsohl bidder).
Opener passes 3NT with a spade stopper or a good club fit,
otherwise bids 4C (possibly 5C).
A free two-level suit bid is natural and non-invitational:
South West North
1NT 2C 2D/2H/2S - natural, sign-off
A free suit bid at the three level is a transfer bid with a very
weak hand or a game-going hand, never an invitational hand. A bid
of the suit below the opposing suit is a transfer to the suit above
the opposing suit, and a cue bid (with one exception) is Stayman:
South West North
1NT 2C 3C - Stayman
3D - transfer to hearts
3H - transfer to spades
3S - transfer to diamonds
4C - Gerber
4D/4H - Texas transfer
4S - mild notrump slam try
4NT - strong notrump slam try
When a suit could have been shown naturally at the two level, a
three-level transfer to that suit is usually based on a strong
hand. Responder could be weak, however, wanting to preempt the
bidding with an extra long suit. Opener is permitted to jump in the
indicated suit with four trumps and a good hand.
The 3S transfer to diamonds, probably forcing opener to the four
level, has to be based on a strong hand (a weak hand would have
just bid 2D), but it implies either no club stopper or a weakish
suit (else why not just respond 3NT?). If opener bids 3NT over 3S
in this auction, he must have clubs stopped or a good fit in
diamonds. Otherwise he must bid 4D.
South West North
1NT 2S 3H - transfer to clubs
Here opener can bid 3S if in doubt whether to bid 3NT or 4C.
Responder can take this as asking for a partial stopper or better
in spades, without which he must not bid 3NT.
A transfer to a major followed by a 3NT bid is the standard way of
describing a balanced hand with a five-card major. This sequence
says nothing about the opposing suit. With no stopper and only a
doubleton in support of the major, opener will have to use his
judgment in deciding whether to pass or bid four of the major
(remembering that an opposing overcall is seldom based on a solid
suit, with which opponents tend to pass in the hope of defeating
a notrump contract).
When the overcall is in diamonds, 3C is Stayman and 3D is a
transfer to hearts (the exception to the cue bid's being Stayman):
South West North
1NT 2D 2H/2S - natural, sign-off
2NT - Rumpelsohl
3C - Stayman
3D - transfer to hearts
3H - transfer to spades
3S - transfer to clubs
Using 3C as Stayman lets opener bid 3D to deny a major, enabling
responder to show a five-card major if he has one.
South West North
1NT 2H 2S - natural, sign-off
2NT - Rumpelsohl
3C - transfer to diamonds
3D - transfer to spades
3H - Stayman, four spades
3S - transfer to clubs
South West North East
1NT 2S 2NT - Rumpelsohl
3C - transfer to diamonds
3D - transfer to hearts
3H - transfer to clubs
3S - Stayman, four hearts
Over the 3H transfer to clubs, opener can bid 3S if in doubt
whether to bid 3NT or 4C. Responder can take this as asking for a
partial stopper or better in spades.
Responder can show a second suit after transferring:
South West North East
1NT 2C 3H Pass
3S Pass 4H/4D - second suit
When responder shows spades and hearts via a transfer sequence, she
is probably 5-5 in the majors and not interested in slam. Opener
must pass 4H or bid 4S. With slam interest, responder shows a major
two-suiter via Stayman:
South West North East
1NT 2C 3C Pass
3D Pass 3S - forcing
3NT Pass 4H - slam interest
This sequence is preferred with slam interest because it gives
opener a chance to make a notrumper cue bid in support of spades.
With a good fit and good support for hearts, opener can bid on over
the 4H bid. It does result in a lead through opener's strength in
the opposing suit, so responder might prefer to transfer with, say,
two small cards in the opposing suit.
Responder uses the Unbalanced Heart Convention (UHC) with an
unbalanced two-suiter that includes hearts and a minor:
South West North East
1NT 2S 3D Pass
3H Pass 3S - UHC, not a cue bid
3NT Pass 4C/4D - second suit
4H - six hearts, slam interest
The 4H bid shows at least six hearts and slam interest, in an
unbalanced hand. If not interest in slam, North would have made a
Texas transfer over 2S. If balanced, she would have raised 3H to
4H, also showing slam interest.
There are two ways to show a one-suited hand with spades:
South West North East
1NT 2C 3H Pass
3S Pass 4S
North has six or more spades, balanced hand, slam interest. He
would have used Texas with no slam interest. With a strong un-
balanced hand he uses this Stayman sequence:
South West North East
1NT 2C 3C Pass
3H/3D Pass 3S Pass
3NT Pass 4S
Bidding this way gives South an opportunity to make a notrumper
cue bid, which could lead to a good spade slam if it strikes
responder well.
There are also two ways to show long hearts:
South West North East
1NT 2D 3C Pass
3H Pass 4H
The 3C response is a transfer to hearts, and the 4H rebid shows six
or more hearts, slam interest, balanced hand. North would have used
Texas (a 4D response) with no slam interest, and with an unbalanced
hand he would have used the Unbalanced Heart Convention (UHC) to
give opener an opportunity to make a notrumper cue bid:
South West North East
1NT 2D 3D Pass
3H Pass 3S Pass
3NT Pass 4H
Negative Doubles
The negative double is recommended as a companion to Rumpelsohl.
Like Rumpelsohl, negative doubles apply only against a natural
overcall (through 2S, at least).
A negative doubler must have at least 8 HCP, maybe 7 HCP with a
good suit, since he must be able to support a 2NT contract if
opener bids it. A double of 2C is permitted with only 6 HCP,
provided responder has at least four cards in each unbid suit.
(Opener must bid 2S, 2H, 2D, or pass the double). Since opener
may pass the double with four cards in the opposing suit, don't
double if you would not welcome a pass.
In response to a double, opener may make a jump rebid with a
maximum. He might not jump with a maximum, however, if the
overcall presents some danger to a game bid. He would probably
not, for instance, jump to 3NT without a double stopper in the
opposing suit. He is not allowed to bid notrump when responder
doubles 2C. If responder wants to invite game in notrump after
doubling 2C, he can bid 2NT and then opener can pass or bid 3NT.
A negative double of one major implies four cards in the other
major, and not enough strength for game-forcing Stayman. A
negative double of a minor implies both majors, but may be a sort
of Stayman with one major only and another bid in the hip pocket
in case opener bids the other major.
South West North East
1NT 2D Dbl Pass
2H/2S - four-card major, minimum hand
3H/3S - four-card major, maximum hand
Pass - good diamonds, probably no major
2NT - no major, minimum or poor diamonds
3NT - no major, maximum hand
3C - five clubs, no diamond stopper
When opener responds to the double with a minor suit, he denies a
stopper in the opposing suit.
When a negative doubler follows with a (game-forcing) cue bid, he
denies a stopper in the opposing suit. Opener must then further
describe his hand in some way, bidding notrump only with the
opposing suit stopped:
South West North East
1NT 2D Dbl Pass
2H Pass 3D - no diamond stop
3H - five hearts or four strong, no stopper
3S - four weak spades or three strong, no stop
3NT - diamonds stopped
4C - four clubs, no diamond stopper
A notrump bid following a negative double is natural (even 4NT).
When an Opponent Makes an Artificial Overcall
-- If the overcall shows two suits, see the chapter DEFENSE VS TWO-
SUITED CONVENTIONS in the book "Marvin's Conventions and Treat-
ments."
-- If an overcall of 2C shows a one-suited hand with an unspecified
suit ("Hamilton") a double replaces Stayman and all bids have the
same meaning as if the overcall had not occurred. Since 2C is
forcing, you can pass with a good hand if hopeful of doubling for
business on the next round:
South West North East
1NT 2C Pass 2D - forced bid
Pass Pass Dbl - business
2H/2S - four-card suit, weak
West's pass of 2D indicates that his suit is diamonds. If North
has a good hand, he must either double 2D for business or make a
strong bid like 2NT or a jump. A minimum reopening bid in a suit
is not invitational. It tends to show a four-card suit because a
five-carder would have been bid immediately. It also implies
support for the next higher suit if opener is short in responder's
suit.
South West North East
1NT 2C Pass 2D - forced bid
Pass 2H Dbl - business
2S - four-card suit
North has S-KJ32 H-76 D-1032 C-QJ54. South can bid 3C with a
doubleton spade and a club suit.
When the 1NT Opening Gets Doubled
-- If the double is natural, not conventional, you can redouble
with as little as 6 HCP. Opener must be told of the 6 HCP or more
so he can double an opposing bid more easily.
Suit responses over the double are weak at the two level, invita-
tional at the three level:
South West North
1NT Dbl 2C/2D/2H/2S - natural, weak
3C/3D/3H/3S - natural, invitational
The jumps show a hand that is distributionally strong but weak in
high cards, considering the failure to redouble.
A 2NT response is artificial, implying a two-suited hand. Opener
assumes that responder has a weak hand with both minors (unusual
notrump), but if responder does not pass opener's minor suit bid
then her next suit bid shows a strong (distributional) hand and is
forcing:
South West North East
1NT Dbl 2NT Pass
3C Pass 3S Pass
3NT Pass 4H
North has a two-suited hand, distributionally strong. The 2NT
response is the only way to make sure she gets a chance to show
both suits. A 3D bid over 3C would also be forcing, probably based
on a hand with long diamonds and a shorter major (Stayman is not
available here).
-- If the double is conventional, showing a one-suited hand, suit
unspecified, a redouble promises only 6-7 HCP, but could have more.
Otherwise the double is ignored and all bids retain the same
meaning as if it had not occurred. All conventions are on: Jacoby,
Texas, Gerber, Stayman, etc. With 8-9 HCP and a four-card or
longer major, it may be better to make the normal response rather
than redouble, to ensure that a major suit contract is not missed.
Since the double forces a 2C bid by fourth hand, another option is
to just pass over the double with a good hand, then make a strong
move (business double, 2NT, or jump) on the next round. A minimum
suit bid after passing, even when not reopening, is weak:
South West North East
1NT Dbl Pass 2C
Pass Pass 2D - weak, just reopening
South West North East
1NT Dbl Pass 2C
Pass 2D 2H/2S - just competing
North's major is probably a four-carder. She would have transferred
on the first round with five.
-- If the double shows two specific suits (e.g., both majors), the
countermeasure known as "Unusual over Unusual" may be used: A bid
in the higher of the opposing suits shows a good hand featuring the
higher "unbid" suit, usually a six-bagger, while a bid in the lower
of the opposing suits shows the lower "unbid" suit. A simple new
suit bid is therefore not invitational. A redouble shows "cards,"
at least 6 HCP:
South West North
1NT Dbl* 2S - diamond suit, invitational
2H - club suit, invitational
2NT - mildly invitational
3C/3D - not invitational
Rdbl - 6 HCP or more
* majors
If South lacks support for the suit indicated "invitationally," he
signs off by bidding North's suit. With a fit he bids 2NT (expres-
sing doubt, probably with an unstopped major) or 3NT.
-- If the double shows two non-specific suits (e.g., "both majors
or both minors"), counter with the same tactics as against Brozel,
described above.
When a 2D Response to Stayman Gets Doubled
South West North East
1NT Pass 2C Pass
2D Dbl
Responder's actions are similar to opener's actions when a Stayman
2C bid gets doubled:
-- With four diamonds headed by an honor, or better, he redoubles.
-- With three diamonds to the queen or better, or four small, he
passes.
-- With less in diamonds, he makes his normal bid.
With 8-9 HCP and a five-card major to show, responder may choose
to bid the major rather than pass or redouble. Otherwise the major
could be shut out if opener bids 2NT, because responder would have
to pass.
With a game-going hand or better responder can safely pass or
redouble, since he can bid a five-card major at the three level
(forcing) if opener bids 2NT.
South West North East
1NT Pass 2C Pass
2D Dbl Pass Pass
Rdbl - natural, wanting to play 2D
2NT - minimum hand, no four-card major
2H/2S - four-card major previously repressed
(possibly a strong three with no
diamond stopper)
Pass is not permitted
North's pass shows at least Qxx or four small diamonds, so the
redouble is to play. A pass by South is impossible here because
North's hand is unlimited. The score resulting from making two
diamonds doubled might not be enough to make up for a missed game.
When Responder's Major Suit Rebid Gets Doubled
South West North East
1NT Pass 2C Pass
2D Pass 2H/2S Dbl
This is probably one of those occasions when North is deceptively
bidding a non-suit. South should redouble with support that
includes a stopper, pass with no stopper, bid notrump with a
doubleton stopper or stoppers. If South passes, no bid by North in
another denomination is forcing, so she must not make a minimum bid
with a game-going hand:
South West North East
1NT Pass 2C Pass
2D Pass 2S Dbl
Pass Pass 3C/3D - sign-offs
3H - invitational
3S - partial spade stop
Rdbl - to play
South has denied a spade stopper with the pass. The 3S bid can't
be natural, so it asks for a partial spade stopper, with which
South bids 3NT. The 3C and 3D bids are sign-offs. The 3H bid is
unlikely--what sort of hand could North have? Maybe S-65432
H-KQJ108 D-Q3 C-6.
When A Transfer Bid Gets Doubled
South West North East
1NT Pass 2D/2H/2S Dbl
-- With a partial stopper (e.g., Qx, Jxx) or worse in the doubled
suit, opener passes. Responder should play the hand, if possible,
so that the doubler will be on lead. If the double gets passed
around, responder can redouble to force opener to bid the indicated
suit. The redouble says nothing about the opposing suit, and of
course responder may be busted.
To invite game, responder can "cue bid" the doubled suit (forcing
the transfer at the same time) or jump in the indicated suit. If
responder merely bids the indicated suit at a minimum level,
perhaps holding something like Qx in the doubled suit, opener must
pass.
-- With a single stopper or better, opener redoubles if he doesn't
want to accept the transfer.
-- A suit bid by opener (accepting the transfer) is non-committal.
He may or may not have a stopper in the doubled suit.
When a Transfer Bid Gets Overcalled
South West North East
1NT Pass 2D 2S
Opener can bid only with a maximum and good support for responder's
indicated suit (hearts, in this auction). Otherwise he must pass,
since responder could have a bust hand. Or he can double, if he is
confident of defeating the contract with little help from respon-
der.
A second suit is not forcing if the bid follows an opposing
overcall, and a double is artificial, a game try. Bidding the suit
is merely competitive, not invitational:
South West North East
1NT Pass 2H 3C
Pass Pass 3D/3H - weak
Dbl - interested in game
3S - not invitational
If North were to pass with a fair but not invitational hand
containing six spades, or a weakish 5-5 with which he planned to
pass 2S, South would probably have to pass also. North therefore
competes with a three-level bid. With an invitational hand, or a
game-going two-suiter, North must double. All the double says is,
"I have at least a game-invitational hand:" An invitational two-
suiter is not shown via Jacoby, so a new suit bid after the
double is forcing to game.
Suppose the overcall comes after a double showing a one-suited
hand:
South West North East
1NT Dbl 2H Pass
2S 3C 3D/3H/3S - weak
The conventional double showing a one-suited hand is usually
ignored by responder, and all bids retain the same meaning as if
the double had not occurred. The 2H bid is therefore a transfer to
spades. Any three-level bid by North in this situation is merely
competitive, not invitational. Responder may choose to redouble
with 8 HCP or more, but with game prospects and a four-card or
longer major it may be better to make the normal response rather
than redouble.
South West North East
1NT 2C 2D Pass
2H 2S Dbl Pass
2NT - minimum, poor hearts, spades stopped
3NT - maximum, poor hearts, spades stopped
3H - minimum hand, heart support
4H - maximum hand, heart support
3C/3D - poor hearts, no spade stopper
Pass - short hearts, good spades
West's 2C bid was "Hamilton," showing a one-suited hand. This
convention is ignored (except that a double is Stayman), so 2D is
a transfer to hearts. The 2S bid reveals that West's suit is
spades. North doubles (artiificially) to show a hand of game-
invitational strength or better. South then bids according to his
hand, as shown. If North next bids a new suit, that is forcing to
game (showing a two-suiter via Jacoby is a game force), but a 3H
bid over opener's 2NT is not forcing.