Source: Mr Bridge
This maxim applies mainly when playing teams or rubber, when it is essential to defeat contracts.
You open 1
and LHO doubles. RHO bids 1NT and LHO raises to 3NT. You lead the ten of clubs. On the first trick partner plays the five and declarer wins with the jack. Next declarer plays the queen of clubs. You had better not duck that as you can see declarer can simply run for home with four spade tricks, three diamond tricks and two club tricks. Having taken the ace you can see that declarer has nine tricks ready to run. There is only one chance to beat the contract, which is to cash four heart tricks. This dictates putting partner with the king of hearts; you should ‘assume you can beat the contract and lead the heart five. The full deal:
You risk giving an overtrick but, at teams, it is a small price to pay for the chance of defeating the contract.
You lead the jack of diamonds. Declarer wins with the king in dummy and, at trick two, runs the jack of hearts to your king, partner following with the two. Declarer surely has plenty of tricks for his contract so desperate measures are called for. If you assume you can beat the contract, there is only one chance and it may seem unlikely. You can play declarer for a bare king of spades and lay down the spade ace hoping to take four spade tricks. The full deal:
Now you are playing rubber bridge:
Your LHO opens 1NT (12-14) and RHO raises to 3NT. Partner leads the spade nine (top of nothing). Declarer wins the first trick with the king. At trick two, you are in with the diamond ace. Desperate measures are in order. Declarer again has plenty of tricks so you must take at least four now if you are to beat the contract. You must try a club hoping partner holds the ace but does it matter which? If partner has fewer than three clubs, it is hopeless and, if partner has four clubs, it does not matter which one you lead. So focus on three clubs with partner. It is vital to switch to the club jack — a ‘surrounding’ play. The full deal:
On the jack of clubs switch, you cash four clubs to defeat the contract. So (playing rubber bridge or teams):
Assume you can beat the contract!