# Different kinds of "two direction" finesses in bridge?

I once read in a book about a "backward" finesse. You, declarer, have AJ9, and dummy has Kxx. Ordinarily, you would finesse twice from dummy toward AJ9. Except that your left hand opponent has indicated by a bid (or double) that he has the queen. If that's the case, you apparently finish "backwards" by leading the J, and covering with the K in dummy if the left hand opponent covers. Then you lead back an x to the A9 on the theory that right hand opponent is more likely to have the T. Why is that?

Another, apparently similar type of finesse is what I call a round trip finesse. You have K854 opposite QT32, and you're apparently finessing for the A, J, and maybe the 0.

How do you decide which way to finesse for an ace?

So you finesse toward the QT32, then back toward K854.

A third kind of finesse is sometimes called a two way finesse. That is, you have ATxx in hand, dummy has KJxx, and you are finessing for the queen. By counting, or other means, you determine that West/East is short in the suit. Then you win the K/A, to drop a presumed singleton, and then finesse the other way for the queen.

All of these finesses differ from what I call "one way" finesses, low in one hand toward, say AQ, or AQT.

What are the rationale behind the two directional finesses? Is the two way finesse a special case of the "one way" finesse or more like the other two directional finesses. And is the reason for a two directional finesse the fact that opposing honors are more likely to be split than to be concentrated in either opposing hand?

The simple, unhelpful reason/rationale is that it gives you the best chances under the circumstances.

For instance

Kxx

AJ9

You need 3 tricks and know that LHO has the Q. Your best shot is to play RHO for the Ten, (which is ~50% assuming no other information is given). Playing the J first sets up the finesse position for the Ten. (Consider a similar one way situation, xxx opposite AJ9. Needing two tricks, you first play to the 9)

You can try playing the AK to drop the singleton Q or doubleton QT, but that is inferior in terms of chances.

I remember reading a book where in one of the problem hands, the right play in trumps was to finesse one way, and if that wins, repeat the finesse the other way! (I might add the hand later if I remember it).

Not sure if that helped.

The key point is that you have a QT minor "tenace" in dummy (over the Jack) that you want to lead to.

If the suit is divided 3-2, you'll make two tricks, one with either the Q or K, the second with a "long" low card. So let's worry about the 5-0 and 4-1 distributions.

Lead low to the QT. If West shows out, East has five cards, AJ976. Play the Q, which (probably) loses to the Ace. When you are back in dummy, lead the T to the K8x through J976. If J covers, win with the K, then lead from dummy through 9xx to 8x next time. Otherwise T and K win two tricks.

If West plays, duck if he plays the Ace, otherwise cover with the Q. If East shows out, the suit is divided 5-0, and you will win two tricks with the K and Q (if West plays the A), or Q and T on finesses.

Let's say the suit is divided 4-1 either way, which is possible if both follow. The worst that can happen is that West plays low and East captures your Q with the A, singleton or not.

When back in dummy, lead low toward your K8. If East shows out, West has J9x. After winning with the K, lead low toward Tx in dummmy, with the T scoring the second trick.

If East plays, capture the J or 9 with the K. Then your T and 8 are equals against the J (and the T beats the 9).

Otherwise finesse the 8. If West show out, you win a trick with the 8 and later the K. If West can take the 8, the suit is divided 2-3, and you will win two tricks with K and the fourth card.