Dormer on Discovery

Discovery at Trump Contracts

Generally speaking, bridge is not a game where you are obliged to make up your mind in a hurry (although sometimes it seems that way). When there is some kind of choice to be made — such as whether to finesse or play for the drop — there is no particular merit in going at it like a bull in a china shop. In bridge, he (or she) who hesitates is less frequently lost, and the proper approach is to postpone decisions until you have discovered, the maximum about the opponents’ hands.
Last month we considered ‘discovery’ at notrump. The snag with notrump is that frequently there are too many suits declarer cannot safely touch. At a trump contract, however — and especially if declarer has a really strong trump suit — this difficulty is not usually present. Getting down to cases, consider the following hand:

Dlr: South ♠ J 9 3
Vul: None A 7 6 4
8 2
♣ A 10 7 3
♠ A K 7 6 4 2
K 3
K 4
♣ K J 5
East South West North
1♠ Pass 2♠
Pass 4♠ All Pass

West leads the 6, which East wins with the ace. East returns the 5 and West plays the three under declarer’s king. Declarer cashed the ♠AK and succeeds in catching the doubleton queen. How should he proceed?
At a notrump contract, declarer would no doubt rattle off his spades and eventually cash his winners in hearts and clubs in hope that either the ♣Q was doubleton or someone had become squeezed. He could not safely play the hand in any other way, and more often than not he would wind up with just 11 tricks.
At a spade contract, though, the element of trump enables declarer to employ a discovery play: after ♠AK he plays three rounds of hearts, ruffing the third. Then he crosses to the ♠J and ruffs dummy’s last heart.
From the play to the first two tricks, declarer has already placed West with five diamonds. West is also known to have had two trumps. If he happens to show up with four hearts, he will become marked with only two clubs, and the odds will then heavily favor playing East for the queen, since he will have started with twice as many clubs as West. In the same way, if East should happen to show up with five hearts, he would be marked with only two clubs, and the finesse would be taken against West.
When the opponents have bid a suit, it is usually possible to judge how many cards each of them has in it. A simple discovery play in one of the remaining suits may then prove especially profitable. A case in point:

Dlr: West ♠ 4 2
Vul: Both 10 8 7 3
A Q 6 2
♣ K Q 6
♠ K Q J 10 6 5 3
9 4
♣ A 9 4 3
West North East South
1 Pass 2 3♠
Pass 4♠ All Pass

West leads the K and South ruffs. The ♠K loses to West’s ace, South ruffs the heart return and draws a second round of trumps, to which the opponents follow. He then takes a losing diamond finesse and is obliged to ruff another heart.
The average player will now decide it is high time to tackle clubs, and accordingly, he will cash the K-A of the suit. For the sake of argument, we will suppose that West drops the jack on the second round. Declarer may hem and haw and huff and puff, but in the end he will be forced to guess whether the suit is dividing evenly or whether East has the 10-x remaining. In effect, he will either get lucky and make a precious overtrick, or not get lucky and make only 10 tricks.
A resourceful player, however, will invariably make 11 tricks. After taking the losing diamond finesse and ruffing the heart return, he will cross to dummy with a diamond, ruff a diamond, reenter dummy with a club, and ruff a fourth diamond with his last trump.
In this way he discovers how the opposing diamonds are divided. The trump distribution is already known and a picture of the heart distribution should have also emerged, both from the bidding and from the way the defenders have played the suit. No doubt South will have little difficulty in placing West with five hearts and East with four.
Consequently, when declarer eventually shapes up to the club guess, he can hardly go wrong. If West has shown up with four diamonds, he will be marked with only two clubs and the third-round finesse of the 9 will be bound to succeed. If, however, West has shown up with only three diamonds, the clubs will be 3-3, and declarer should accordingly play for the drop.
Discovery plays may also be employed to gain a clue to the distribution of the trump suit itself. There are dangers, naturally, in tinkering around with side suits before trumps have been drawn, but at matchpoints, much more so than at IMPs or rubber bridge, it often pays to accept the risk. At that, there are many cases where a discovery play of this type can be made with very little risk indeed. For example:

Dlr: South ♠ A 10 7
Vul: E-W K 9 5
K 7 4 3
♣ 6 4 3
♠ K J 9 8 3
A Q 6
A 8 6
♣ K Q
East South West North
1♠ Pass 2♠
Pass 4♠ All Pass

West leads the ♣J, which East wins with the ace. A low club is returned and West plays the 10 under South’s king. Clearly, declarer is safe for 10 tricks, and the only real question is whether he can locate the ♠Q and make 11.
From the play to the first two tricks, it seems quite possible that West has led from the J-10 bare of clubs, in which case East has six of them. If so, declarer would certainly be well advised to abandon the normal percentage play in trumps, which is to cash the ace and then take a finesse against East. Rather, since if East has six clubs he may be expected to be short in trumps, the proper play would be to lead a trump from the South hand and take the first round finesse against West. (It would not be correct to cash the king first. Cashing the king would gain only if East had the bare queen, but would cost a trick in the far more frequent instances where East has a small singleton.)
However, although West may very well have started with the doubleton ♣J 10, he may also have a longer sequence, in which case there will be absolutely no grounds for assuming that East is short in trumps. You would certainly get a very cold look from your partner if you played the trumps in backwards fashion and lost to East’s queen because you had drawn the wrong conclusion about the clubs.
Fortunately, the problem can be solved. At trick three you cross to the K and lead dummy’s remaining club, throwing your diamond loser on it. If West shows out on this trick, you can go ahead with your reverse play in spades, but if West should follow suit, you can revert to the normal percentage play in trumps.
Admittedly, there is a slight risk involved in this line of play, since the opponents might maneuver a ruff on you while you are poking around. But even though your grandmother might not approve, it is of such stuff that winners are made at the matchpoint game.

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