Principle of Restricted Choice

How should you play a suit when you see an opponent play an honour under your ace or king on the first round of the suit? You should watch carefully during the play in case an opponent plays an honour when a low card would have been the normal play.

If you assume the opponent who played an honour has played that honour because it is a singleton, you can envisage the entire layout of the suit.

Example:                       Declarer   ♠A8742              Dummy    ♠Q1065

You are west and the declarer in 4♠. With ♠A opposite ♠Q (not supported by ♠J), your best play is to lead ♠A. Under ♠A, north plays ♠3 and south plays ♠K.

South’s ♠K looks like a singleton. You now play ♠2 from west. When north plays ♠9, you should finesse to win east’s ♠10 as south will have no spades left. East’s ♠Q will now take north’s ♠J. You make all the tricks.

When you are playing a suit in which you hold eight or more cards including the ace, king and ten, watch to see if an opponent plays the queen or jack on the first round of the suit.

If an opponent plays the queen or jack on the first lead of the suit you should assume the opponent who played a queen or jack has a singleton.

When an opponent follows suit with the queen or jack on the first round of the suit, it is more likely that opponent has a singleton honour than both missing honours.

This theory is known as the Principle of Restricted Choice.

Remember that when missing the queen or jack in the suit, you should first win the ace or king in the hand without the ten, leaving the other top honour with the ten so you can finesse on the second round if necessary.

Example:                       Declarer    ♠A10742             Dummy    ♠K653

You are west and the declarer in 4♠. Keep ♠A and ♠10 for the second round of the suit. So lead ♠2 from west. When north plays ♠Q, win east’s ♠K. South plays ♠8.

Why did north play ♠Q on your ♠2? The Principle of Restricted Choice indicates that north’s ♠Q is likely to be a singleton.

You now lead east’s ♠5 and south plays ♠9. Should you play ♠10 or ♠A?

Play ♠10. On the second round of spades you should finesse. Your ♠A will now take south’s ♠J.

Sometimes you need to organise the lead to take the finesse on the second round of the suit.

Example:                       Declarer    ♠AK10742                       Dummy    ♠653

You are west and the declarer in 4♠. You lead ♠A, north plays ♠J, east plays ♠3 and south plays ♠8.

Don’t play ♠K! North is likely to have a singleton ♠J, so cross to east’s hand with a winner in a different suit. Once you have the lead in east, play ♠5. When south plays ♠9, finesse to win ♠10.

West’s ♠K will now take south’s ♠Q.

Sometimes north will have started with both ♠Q and ♠J and you will lose the second round to north. Don’t ring me up if this happens! Nothing I teach works all the time, just most of the time!

© 2022 John Roberts