In contract bridge and similar games, a finesse is a technique which allows one to promote tricks based on a favorable position of one or more cards in the hands of the opponents. If one can lead up to a finessable position such as ace-queen, an additional trick can be won if the king is positioned in front of the combination of ace and queen.
A more precise definition of a finesse would be: A play that attempts to win either the current trick or a later trick with a certain card of the suit led, although the opponents hold a higher card in the suit, by taking advantage of the position of the particular cards.
A finesse is said to be on or off depending on whether or not the finessable honor is favorably placed (onside) or not (offside).
Many finesses involve a combination of non-touching honors in the same hand, called a tenace.
Other times it can gain one trick:
South leads a spade to the 10. Assuming it loses, he reenters his hand and then leads another spade to the jack. North-South will take two spade tricks if West has either the king or the queen, or both (probability about 75% in the absence of any information), but only one if East has both (25%). However, this combination lends itself to an endplay - if one can be effected two tricks are guaranteed.
Similarly, a triple finesse is possible, and occasionally desirable, with a holding such as A-Q-10-8. This would be a low-probability desperation play if four tricks are needed in the suit, but two or three will probably be made.
South leads a spade, West follows with the 3 or 6, and then the 7 is played from dummy. In this situation, of course, South does not expect the 7 to win the trick, although that is a distant possibility -- the 7 will win if East has a singleton 6 or 3, which would mean that West has blundered by playing his lowest card. The more likely purpose of this play is to keep West off lead. The term deep finesse used in this context is descriptive, but also has a somewhat humorous connotation, the approximate meaning being "doomed finesse."
Examples 1 and 2 play the same way. If the declarer intends to finesse, it is normally not desirable to start by leading to the queen: if the finesse is on, the hand would still have to be reentered in order to repeat the finesse. Instead, if the jack is led first, and West plays low, the small spade from dummy can be played. This is called running the jack. Now the lead is still in hand and the finesse can be simply repeated by leading low to the queen. If West does have the king and covers the jack with it, then the ace is played and, since Q and 10 are high enough, they can be cashed for the two remaining tricks.
Examples 3 and 4 show that when leading high for a finesse, the honors in the led-to hand do not have to form a tenace provided the honors in the other hand compensate it. Example 3 can be played exactly like examples 1 and 2, by running the jack (or queen or 10). In Example 4, a double finesse can be taken by running the 10 (or 9).
Counterexample:Here, the lower honors do not provide sufficient compensation, as the ten is missing. Even if the king is with West, he can deny three tricks to the declarer by simply covering either queen or jack at any time. Thus, (except in the unlikely event of singleton king), the declarer is entitled to only two tricks in the suit no matter how he plays it. The finesse can be attempted only as a tactical move, in order to gain a tempo or manage entries.
In this example, hearts are trumps and South's 2 is the last one remaining, and the lead is with North (dummy). Then North-South can take all tricks if East holds the ace of spades. A spade is led from the North hand; if East plays low, a diamond is discarded and the lead is repeated. If East never covers, North-South get three spade tricks and a trump. If East plays the ace, South trumps and leads a club to return to the dummy, which is high, so taking two spades, a trump, and a club trick.
If South begins by leading the king-queen, he learns on the second trick that East has no more spades. The finesse of the ten is now a sure thing.
Start by playing the king of spades (or if in dummy, leading the 2 to the king) and then running the jack; this makes three spade tricks if East has the singleton queen or if West has the queen, and if that's not the case, then East will be on lead. Or start with the ace and 10, making three tricks in the opposite situation, or leaving West on lead. The decision of which way to finesse might be based on which opponent is more likely to have the queen, or on which opponent it would be safer to give the lead to, if need be. And there is always the option of not finessing at all.
This holding similarly presents a two-way finesse, but along with a suitable entry it will always produce 5 spade tricks no matter how the opponents' spades are placed.
Play the ace on the first spade trick. If both opponents follow suit, the jack must drop and no finesse will be needed; if one opponent shows out, there is a marked finesse available against the other. For example, if East shows out, a small spade is played to the queen, and the K and 10 score via the marked finesse; finally the South hand is entered in another suit and the 13th spade is cashed (or if spades are trump, used for a ruff).
But weaken the holding slightly and the finesse is no longer two-way:
Now the opponents have the jack and 10. Here, if entry considerations permit, the queen must be played first to discover if the spades split 4-0. Then, if they are 3-1, the play goes as before.
But if the spades split 4-0, someone has J 10 7 6. If East holds all four outstanding spades, there is nothing to be done; East must take a spade trick. But if West has all four spades, declarer can still take 5 tricks: after East shows out on the lead of the queen, a small spade is led toward dummy for a deep finesse.
The point is that if an opponent might hold two minor honors, such as the jack and 10 here, declarer should not weaken a two-honor holding before it's clear how to use it. In this example, nothing is lost by cashing the queen first, because declarer can never cope with those four spades in East's hand. But declarer can cope with four spades in the West hand, so long as the A-K is retained over West's holding until West has played to the second spade trick.
As noted above, a ruffing finesse is "on" if the opponents' critical honor is positioned after yours, the reverse of an ordinary finesse. Consequently, there is a form of two-way finesse where a ruffing finesse can be taken against one opponent or an ordinary finesse against the other. If there is no other reason to choose one play or the other, the ruffing finesse may be a superior alternative because it allows leading high and retain the lead. For example:
East plays a contract of 4 hearts. After the opening lead of a diamond, he wins the ace and plays the two top trumps; they break 3-2. He leads a spade to the queen, but the finesse is off, and the opponents now cash two diamonds. With a trump still to lose, one down.
Out of luck? Not at all. The contract is cold as long as trumps break 3-2 (and the defense cannot get an early ruff). The correct play is to win the ace of diamonds and to continue with the ace of spades, followed by the queen for a ruffing finesse. If North does not cover with the king, declarer pitches a losing diamond. If North does play the king, declarer ruffs and later pitches a diamond on the jack of spades. Even if the king is with South, declarer loses 3 tricks only, if trumps are 3-2. And if trumps are 4-1 the game will still make if the king of spades is sitting with North. The advantage of the ruffing finesse over the ordinary finesse here is the gain of tempo if it loses.
Against South's 4 contract, West leads the K, removing an entry that might have proven useful later. South leads the 2 and finesses the J. West can see that, with the clubs probably running, South will have no problem if West wins his Q. So West ducks smoothly.
A trusting player sitting South would now lead the 8 to the K, preparing to finesse East again for the Q, but East's discard would come as a shock. After taking the K, South can't knock out West's Q without allowing the defense to take at least two spades, a heart and a diamond.
After the J wins at trick 2, South's only correct play is to finesse West for the Q, even though he has apparently and successfully finessed East for the same card. The point is to guard against West's clever holdup.
The reason for the term Ann Gallagher finesse is found in a New York Times article. Ann Gallagher was a movie actress in the 1930s. She enjoyed bridge, and when she won a two-way finesse she would repeat it in the opposite direction, saying "Now let's see if I'm really lucky."
Free finesses often happen due to the defense guessing wrong about high cards in declarer's hand, especially on the opening lead. But it is also possible to force the defense to give you a free finesse, by endplaying them. Consider the two-way finesse example again, but with an additional card:
Nobody has played any spades at any point, so the defense is known to have 7 of them, and their other card is known to be a heart. Declarer leads a heart, losing to whichever defender holds the high heart; and that defender is now on lead with nothing but spades. North-South will take 3 spade tricks for certain, and declarer need not guess which way to finesse the suit.
Normally, declarer would cash the A and K separately. However, two spade entries to North might be needed, for reasons such as setting up North's side suit or preparing an endplay. If West holds the Q, declarer can reach dummy twice with an entry finesse: lead the 10 from hand and finesse the J. If the J holds, the K can later be overtaken by the A for the second entry to dummy. If West is aware of what's going on, though, he can stop it by covering the 10 with the Q. Now the suit is blocked, because the J cannot overtake the K. As with many deceptive plays, declarer should take the entry finesse as early in the play as possible, before the defense realizes it must play second hand high to block the suit.
The standard play would be to finesse East for the queen, either before or after cashing dummy's ace. But South may have reason to believe that West has the queen, perhaps from the bidding. So South begins by leading the jack from hand. Then:
There are three reasons that South might choose to play this way, rather than taking the normal course of finessing East for the queen:
The bottom line is that in similar positions, the first declarer's play must be a low card through the hand with two cards; thus, he must guess the position to collect three tricks in the suit.
In order to take three spade tricks, the declarer must first lead low to the dummy's 9, losing to East's 10. Next, the ace drops the jack, and leaves a simple-finesse position against East's queen in the third round. Note that this maneuver will work with any doubleton honor with West, but will cost if West holds QJx, QTx, or JTx.
This specific case of a free finesse is important enough to have its own name (after the city of Bath in England). It occurs when the declarer holds a suit headed by A-J-x and the left-hand opponent leads the king or queen of the suit. If the declarer ducks and the opponent now repeats the lead, two tricks will be won with the ace-jack.
The Bath coup is not just a deceptive play. Even if the suit is not continued, the declarer gains a tempo, since he still has a sure stopper in that suit.