Which calls can a player make during a contract bridge auction?
Card editor of the London Field W.H. Whitfeld published this bridge problem in 1885. South is declarer and has the lead with hearts as trump. With a sophisticated finesse, South can win every trick. South begins by leading the ace of diamonds, which, depending on what the opponents discard, opens a possible finesse of North's jack of diamonds. Next, South passes the lead to North with a spade that North trumps. North then leads the last heart, and South discards the 10 of clubs. With the lead of the last trump and then the ace of clubs, the defenders are presented with an insurmountable dilemma. East must hold two diamonds or South takes the last two tricks in the suit by discarding a spade. However, in order to hold on to two diamonds, East must discard the jack of spades, which in turn would force West to hold the queen of spades. Since West also needs the queen of diamonds and the jack of clubs to avoid losing a trick, a discard from any of the three suits will allow South to win all of the remaining tricks by an appropriate discard.
In the game of contract bridge, players take turns making calls during the auction. A call must be one of the following four options:1
- Pass: Indicates that a player does not wish to make a bid at that time.1
- Bid: A commitment to win a specific number of odd tricks (beyond the first six) with a designated trump suit or at no trump. Each new bid must be higher than the previous one by naming more tricks or a higher-ranking suit.1
- Double: A player may double the last bid if it was made by an opponent and has not yet been doubled. This is often used to increase the stakes or, in the case of an informatory double, to communicate information to a partner.12
- Redouble: A player may redouble if their side made the last bid, it was doubled by an opponent, and it has not yet been redoubled.1
Once a call is made, it cannot be changed. The auction concludes when any call is followed by three consecutive passes.1