Sunday, February 25, 2018

Time For: Lebensohl

Time For: Introducing bidding conventions that may not be familiar to local players, but are nearly universal in common usage such as ACBL Bridge Bulletin Standard. Whether or not you adopt the convention -- I suggest that you do! --  at the very least you should know enough about it to understand the opponents' usage.

When our side opens 1 NT, the default assumption is that we can play in notrump unless we find an appropriate fit for a suit contract. But if the opponents enter the auction with a suit overcall, we can't rely on that default without making sure we have a stopper in their suit (or suits). After a 1NT opening and an overcall, there are five missions that responder might need to accomplish:
  1. Show a long suit (5+ cards) with ability to distinguish between nonforcing, invitational, and game forcing hands as much possible
  2. Inquire about 4-4 fits, especially in the major suits (e.g., Stayman)
  3. Show a stopper in the opponent's suit
  4. Ask partner if she has a stopper in the opponent's suit
  5. Collect a juicy penalty when the opponents are bidding on trash.

The standard way to do all these things is via a convention called Lebensohl (sometimes shown as "lebensohl" without capitalization). There are some variations, what follows is by far the most commonly used.

First of all, a double by responder is for penalties; the opponents have wandered in where they don't belong, and we are going to slap their hands soundly.

Lebensohl only applies if the opponents have overcalled. A new suit by responder is nonforcing at the two-level, and game-forcing at the three-level. For other auctions, responder denies a stopper in the opponent's suit unless responder bids 2NT immediately.
  • an immediate 3NT bid shows values for game, but denies a stopper in the opponent's suit. If opener does not have a stopper, the partnership scrambles by bidding four-card suits up the line
  • an immediate cue-bid asks for four-card majors and shows values for game, but denies a stopper in the opponent's suit. If opener does not have a four-card major or a stopper, opener scrambles.

The key bid in Lebensohl is the 2 NT response. The 2 NT bid is artificial, a "puppet" for 3 . That is, opener must bid 3 , and responder will then bid again to clarify the hand. After the 2 NT-3  sequence:
  • a delayed 3NT bid shows values for game and shows a stopper in the opponent's suit. Opener passes.
  • a delayed cue-bid asks for four-card majors, and shows a stopper in the opponent's suit. Opener shows a four-card major if she has one, otherwise bids 3NT safely.
  • three of a suit (lower-ranking than overcaller's) is natural and non-forcing
  • three of a suit (higher-ranking than overcaller's) is natural and invitational
  • responder can pass with a weak hand and at least six clubs
To remember which sequence shows a stopper, the direct bid or the delayed bids (via 2NT), I like the mnemonic "slow shows, and direct denies". Another way to think of it is analogous to the Principle of Fast Arrival, where the slower route shows some extra values (a stopper, in this case).

Time for some examples. We are playing a strong 1NT opener (15-17 HCP) and our right-hand opponent overcalls a natural 2  .

 1 NT - (2 ) - ?
 K x x x x x  Q x x  J x x x
Pass: the normal bid with nothing.

 K J x x x x x  Q x x  J x x
Bid 2 , nonforcing

 K Q x x x x  A x x  K x x x
Bid 3 : asking for a four-card spade suit and denying a heart stopper

 K Q x x K x  A x x  x x x x
Bid 2 NT, then 3  over 3 : asking for a four-card spade suit and showing a heart stopper

 K Q J x x x x  A x x  K x x
Bid 3 : natural and forcing to game

 K Q x x x x x  A x x  x x x x
Bid 2 NT, then 3  over 3 : natural and invitational

 x x x x x  x  K x x x x x x
Bid 2 NT, then Pass over 3 

 x x x x x  K x x x x x x x
Bid 2 NT, then 3  over 3 : nonforcing

 A x   K J 10 x  x x x x  A x x x
Double: this should be fun!

Playing Lebensohl, the following bid sequences must be Alerted after our 1NT opening and the opponents two-level overcall. If an explanation is requested, you can use the following:
  • 2NT  "puppet for 3 ♣, usually promises another bid"
  • 2NT - 3 ♣   "forced by the 2NT call"
  • 2NT - 3 ♣ - 3suit   "nonforcing" or "invitational" as appropriate
  • 3NT   "values for game, denies a stopper"
Note that cue-bids in this sequence do not require an Alert. If an explanation is requested, state that the cue-bid asks for a four-card major, and either shows or denies a stopper (depending on the sequence).
NOTE: Many partnerships do not play Lebensohl after a 2 ♣ overcall, since the opponents have not taken away any bidding space. Also note that most experts nowadays play the double as a negative double for the unbid suits, leaving opener the option to convert for penalties. Make sure you and your partner have an agreement one way or the other.
BONUS MINUTE: Why not just play "stolen bid" doubles? Yes, stolen bid doubles are simple and easy to remember. But with stolen bid doubles:
  • You don't have a way to ask opener for a stopper, unless you give up the ability to ask partner for a four-card major.  
  • You can't play a lower-ranking suit at the three-level.
  • You can't show higher-ranking suits in all three shades of nonforcing, invitational, or game forcing
  • You encourage the opponents to interfere in your auction with impunity. 
  • Like the Black Knight in Monty Python and the Holy Grail, you have lost both arms but gamely fight on... "it's just a flesh wound!"
EXTRA BONUS MINUTE: Lebensohl has been standard among experienced players for decades, but there is a convention that I like even better: Rubinsohl. I think it is technically superior and much simpler to play and remember. The Wikipedia page for Rubinsohl is a good introduction.


-- Ray 
Better Bridge in 5 Minutes. Guaranteed! (or the next one is free)

Monday, February 5, 2018

Tell Them What They Know



5
K 9 7 4 2
9 4 3
A 10 9 8
N
WE
S
K J 6
Q J 5 3
A Q 10 5
K 7

WestNorthYOUSouth
1 
Pass1 NT1Pass2 
All pass
  1. forcing one round

The first three tricks went:
  • Partner's fourth-best  4 to your king
  • Your  7, declarer's  J, partner's  Q, dummy's  A
  •  5 from dummy, you played low, declarer's  Q held, partner played the  2
Then declarer played the  A, partner the  7, and declarer discards a heart from dummy. You have the king and jack of spades. Whichever spade you play, the other one is good. Does it make a difference which spade you play?

ANSWER: Play the  K. Don't give away the spade suit position to declarer by playing the  J.
It would be easy to just play the  J by rote, thinking that it doesn't matter. If you've read previous articles here about helping partner figure out your hand, it might be tempting to play the  J as a suit-preference signal for diamonds. But partner doesn't know for sure that you hold the king; from her perspective, declarer might have started with the  AKQ and is just adding some confusion for the defense (always a good idea for declarer!).

If you play the  J, declarer (who already knows you have the king) will realize that you started with exactly three spades. If declarer has exactly six spades she will clear both remaining spades by leading one more round. But if she thinks partner might have started with four spades to the jack-ten or jack-nine, clearing spades might not be an appealing line of play.

THE PRINCIPLE: All else equal, play the card you are known to hold. This is an important principle for declarer as well as for defenders. When playing to a trick where the opponents already know that you have a specific card in that suit, don't choose some other equivalent card in the suit. Don't reveal extra information about your hand without the clear expectation of some extra benefit.

The complete hand:

5
K 9 7 4 2
9 4 3
A 10 9 8
9 7 2
10 8 6
J 8 2
Q 6 5 4
N
WE
S
K J 6
Q J 5 3
A Q 10 5
K 7
A Q 10 8 4 3
A
K 7 6
J 3 2
-- Ray 
Better Bridge in 5 Minutes. Guaranteed! (or the next one is free)