You are East in this week's deal, defending against 3NT. Partner leads the ♠3. The opponents inquire about your opening leads, and you reply that your partnership plays third-fifth leads in partner's suit. You play a high spade, and declarer wins the trick with the ace. He then passes the ♣10 to you. Plan your defense.

Solution:
Declarer is marked with marked with pretty much all the remaining high cards. He is also certain to have the ♠J, as he would have ducked the opening lead with Axxx in spades. You can count one spade trick, three heart tricks and four diamond tricks for declarer. If you win the club and cash the ♠K, the ♠J will be declarer's ninth trick.

It should be evident that there is no legitimate way of stopping declarer from scoring a ninth trick. If you win the ♣J and play a passive heart, declarer will continue to knock out your club honors, and establish club tricks; you will be restricted to three clubs and one spade. Declarer knows that your partner has a three-card spade suit. What if you make declarer believe that your partner has the other spade honor? You can do this by advancing the ♠10 at trick three. If declarer ducks this, you continue with the ♠9. Once you play the ♠9, declarer can no longer put off his decision. If partner started with Hxx, then declarer must duck again, as partner's honor will now be stiff. Declarer indeed plays a low spade, and you cash three more spade tricks to set the contract three tricks.

In order to execute this defensive coup, certain preparations have to be made. At trick one, the spade honor you play should be the ♠K, making declarer believe that your partner has the ♠Q. More importantly, at trick two, you should win the ♣10 with the king, and not the jack. If you win trick two with the jack and play the ♠10, ducking the trick may net the defense three clubs and two spades, therefore declarer would have no option but to play the ♠J.

When you lead the ♠10 at trick three and declarer ducks this, you have the option of exiting in hearts and waiting for declarer to make the next move. If he plays another club, you will score three clubs and two spades. However, after a heart switch, declarer can succeed in theory by cashing his red suit winners ending in hand, catching you in a strip-squeeze. In practice, declarer may think that you stopped playing spades because you did not want to expose the spade situation (your partner having honor third of spades), and may continute to play your partner for the ♠Q and go down.

Analysis:
Since this deal does not involve intricate technical details, the double dummy solver does not contribute any additional information towards the analysis of this deal.
Par Contract Analysis:
The par contract on this deal, where both sides are vulnerable, is 4♠X by South, which is two down for -500.

Bridge Baron deal No : N0919-33950-11934-20986-11741-31551