Dormer on Discovery

Discovery of high cards (cont.)

Last week we saw that when declarer is bent on discovering the location of certain key cards in the opposing hands, he can sometimes achieve his goal by first forcing out those high cards that do not affect his contract. In attempting to ferret out this type of information, declarer’s job is made that much simpler if the opponents have entered the bidding. For example, observe how declarer can avoid a guess in the diamond suit by proper play on theis deal:

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

*15-17 HCP
Opening lead: 10
East opens 1NT, indicating 15-17 points, and you, South, become declarer at 3♠. You play low from the dummy on the opening heart lead and East plays the queen. East exits with the ♠A and another trump and, with a certain club loser to come, your problem is to avoid losing two diamond tricks.
In view of the bidding, it would seem that East is a distinct favorite to hold the A, in which case, you would have no choice but to play West for the queen. However, a bit of discovery play may lead to a different conclusion.
From West’s opening lead of the 10 and East’s play to the first trick, plus his failure to return a heart at trick two, it seems likely that East has the K-Q of that suit. You could confirm this diagnosis by ruffing a heart or two, but such a procedure would serve to put the opponents on their guard, and on balance it is probably better to assume the heart situation is as you have read it. Therefore, at trick four you lead a low club from dummy. In the actual hand East will probably play the queen, thus becoming marked with the ♣KQ to go along with the KQ and the ♠A. Since the A would give him a total of 18 points (one more than his range permits), you should now play West for that card.
Note that, to mislead you, East may well play the ♣K rather than the queen when you lead one from dummy. This would not cause you an awful lot of trouble in actual case, since when you next got in you could lead the ♣J and draw the appropriate conclusion when West failed to cover. Nevertheless, a fine defender does try to make the declarer’s lot a less happy one by employing the art of concealment, as it is called. Sometimes the declarer’s attempts at discovery and the defenders’ efforts at concealment may lead to a prolonged battle of wits, as when this deal was played:

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

Opening lead: ♣3
It was clear from the start that the outcome would depend on how South handled the hearts, but the defenders were determined not to make life easy for the declarer. Their campaign began at trick one when East, on the opening lead, inserted the jack rather than automatically putting up the king. The play was perfectly safe, since West could not have underled the ace.
South won and drew two rounds of trumps, ending in dummy, after which he led a club in an attempt to find out a little more about the hand. East took this trick with the king, and the declarer was now inclined to suspect East had started life with ♣KQJ. To muddy the waters still further, East exited with the unsupported ♠K, creating the impression that he held either the A-K or K-Q of the suit.
Now South was not a particularly gullible player, but nevertheless he decided that, since East evidently held so many points in the black suits and had passed originally, he couldn’t possibly have the A. So after ruffing the ♠K, he entered dummy with a trump, led a heart to the jack, and went down a trick.
The reader may have noticed that East’s play of the ♣J in this deal, although made for quite another reason, was also, in effect, a discovery play. The play of the jack from K-J at trick one is in fact one of the most common discovery maneuvers the defenders can safely make, since it reveals whether the declarer has the A-Q in that suit or merely the unsupported ace. Indeed, the third-hand defender should always play the jack from K-J in a situation like this:
 

North (Dummy)
♠ 8 6 4
4 2
A Q J 6 2  East (You)
♣ A 8 3 ♠ K J 3
J 8 7 6 5 3
9 4
♣ K 7

Opening lead: ♠2
Suppose you are defending against 5♣, and West leads the ♠2. You can be quite sure that your partner, if he values his life, has not underled the ace. If you play the king, declarer will win with the ace, but then you will not know what to return when you get in with the king of trumps. There may be to spade tricks for the taking — if West has the queen — or there may not be.
You solve the problem by making the discovery play of the ♠J at trick one. If South wins with the queen, you will know that your only hope is a heart shift.