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This hand came up in the Round-of-16 Vanderbilt match-up betvveen teams captained by Bart Bramley and George Jacobs, at the 2007 St. Louis NABC. Mark Feldman of the Bramley team reached 6 Pik as South (hands rotated for convenience) after a complicated auction, during which the opponents were silent throughout. Plan the play after the Clup Q is led. The scoring is İMPs.

Hint

If diamonds divide 3-2, the hand presents no problems. You should devote your time to thinking about how to protect against possible 4-1 diamond breaks. And, remember, the scoring is IMPs, so you need not worry about giving up overtricks.

Solution

Let us look at some possible lines of play:

Ruffıng Diamonds

When diamonds divide 4-1, you will need to ruff two diamonds (unless the singleton is the Diamond Q or Diamond 9) in your hand in order to set up the suit. If you need to ruff two diamonds and trumps also fail to split, an opponent will be left with more trumps than you and the contract will fail. Therefore, setting up diamonds by ruffıng is not a high percentage line of play.

The Diamond Finesse

Another solution is simply to take the diamond fınesse. The snag in this plan is that if East has four diamonds to the queen, the defense can score a diamond ruff. If you draw trumps before taking the diamond fınesse, you will have no club control and the defense can cash club tricks, should the diamond fınesse fail. The contract is too good to stake it on a 50% chance, so there must be a better line than simply relying on the diamond fınesse.

Cashing Your Top Diamonds

What about playing the Diamont A-K immediately, before drawing trumps? This is a better plan than the previous two and wins vvhenever the opponent with the singleton diamond also has the long trump. However, if the person with four diamonds also has long trumps, then the hand short in trumps will ruff your Diamond K and you will not be able to set up your long diamonds without setting up a long trump for the opponents.

Giving Up a Diamond Trick

The correct play on this deal is to give up a diamond trick early on. However, giving up a diamond trick at trick two would stili allow the opponents to get a ruff if diamonds were 4-1.
To counter this, you must fırst cash the Diamond A and then lead a diamond towards your jack, intending to concede the trick. Whenever diamonds are no worse than 4-1 and spades are no worse than 4-2, this play guarantees the slam.

On this deal, as it was played

in St. Louis, East has four diamonds headed by the queen, but has no counter to your well-thought-out play.

If East wins the Diamond Q at trick three and plays back a diamond, you will ruff high, draw trumps and claim.

If East wins the diamond Q and plays a club, you will ruff in dummy, unblock the spead A, return to hand with the heartK, draw trumps and claim.

Suppose East refrains from playing the diamond Q and lets West ruff the trick. If West returns a club, you ruff in dummy, unblock the spead A, ruff a diamond high, draw trumps and claim. If West returns a heart, you must take care to preserve the heart A as an entry to dummy, and win the heart in your hand with the king. You can then reenter dummy with the spead A, ruff a diamond high, draw trumps, and then use the heard A as an entry to the good diamonds.

Post Mortem

At the other table, Zia Mahmood and Michael Rosenberg reached 7 which is an excellent contract if diamonds split 3-2, a 68% chance. Since diamonds were 4-1 on this deal, 7 spead goesdown, and making 6 spead netted 17 IMPs for the Bramley team, who went on to win the match.

Bridge Baron's Play of the Hand

Bridge Baron did not fınd the optimal play on this deal. Bridge Baron's line was as follows.
Win the club A at trick one;
ruff a club low at trick two;
cash the diamond A at trick three,
carefully unblocking the diamond J along the way;
cash the spead A at trick four;
then play a heart to the king and
draw the outstanding trumps.
It then led diamond 7 towards dummy, found out the had news,
and ended up going down two when it could not recover.

Bridge Baron's line of play relied on either diamonds being 3-2 or there being queen lourth of diamonds with West. This is respectable percentage, but is also a clearly inferior line of play.

Deals like this, fınding safety plays in high-level contracts, are normally a strength of computer bridge play, so what led Bridge Baron awry? The ansvver is that because there are so many different ways this hand can be made, on most layouts, Bridge Baron did not create a fırm plan for the play. It essentially kept delaying its decision on how to play the hand, until it forced itself into relying on diamonds being 3-2.

Think of ali the different possible ways to make this contract: diamond fınesse, dropping a singleton or doubleton diamond Q, hearts being 3-3 and pitching a club loser on the 13th heart, ete. Bridge Baron plays the cards based on double-dummy simulations and therefore alvvays assumes it will go right later in the hand. On a deal like this one, with so many different possible ways to make, it doesn't understand that its plays are eliminating some of its chances and making the contract more diffıcult. Instead, it simply "knows" it is alvvays going to go right later in the hand and considers ali of its plays to be essentially equal.

On this particular hand, it was actually the club ruff at trick two that started the problems. Obviously, the club ruff is not what cost Bridge Baron the contract, so Bridge Baron assumed itwould always make later and didn't see any risk to this play. Similar problems resulted from Bridge Baron's decision to unblock the 0 J at trick three. The contract was technically stili cold, but Bridge Baron had further limited its flexibility.

It was ultimately the cashing of the spade A that sealed Bridge Baron's fate. The problem was that after ruffıng the club at trick two and unblocking the diamond J at trick three, Bridge Baron had put itself into a position where its best percentage play was to rely on diamonds being 3-2 or the diamond Q being onside, so that was the line it took.

Analyzing this deal reveals that Bridge Baron, like many beginning human players, has a diffıcult time when there are too many options available to it. Bridge Baron doesn't plan ahead well enough, so as to combine its chances in the most effıcient way possible. Bridge Baron actually tends to delay making its decision while it can and ends up painting itself into a corner on deals like this. Through a series of technically "double-dummy correct" plays it forces itself into an inferior and single-dummy incorrect line.

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