Perhaps either North or South should have considered bidding the grand slam here, which looks to be about negotiating the trump queen. And if you fail to do that, you strongly rate to go down in six spades on the predictable diamond lead.

However, the problem today is to focus on the best line to make slam after the diamond lead. As a hint, you need to work out what else might cause you a problem in your slam, other than a bad trump break.

The point of the deal is that after winning the diamond ace and negotiating the singleton trump queen to draw trumps in three rounds, you must focus on the quite real chance of a 4-0 club break. After all, West has three spades and at least six diamonds, doesn’t he?

What you must do next is to cash the heart ace and king, then exit with a diamond. If West wins, the club loser disappears on the forced ruff-and-discard. If East wins and returns the club jack, run it to North’s ace. The next club goes to the nine and queen. Now you must return to the table with the spade six (it was vitally important to keep a trump entry to dummy, by not wasting your spade five at any turn, early on in the deal, or else to make your slam you would have had to guess that East has all four clubs). But if you have kept your entry position intact, you can indeed cross to the spade six and finesse against East’s club 10.

At a suit contract, when a defender leads a side suit bid by dummy, it is very often a singleton. Here West led the heart six to dummy's jack and East's queen. Declarer dropped the 10, trying to give the impression that it was he who had the singleton. But East knew that if West had started with a doubleton he would have led the eight, not the six. Therefore South must be concealing the missing card.

At the end of trick one, East had to find a route to four tricks. There were two heart tricks, and hopefully a heart ruff if partner could overruff dummy — but where was the fourth? What other clues had East from the bidding? South’s bid of four spades had essentially ruled out slam. Since North had not yet really limited his hand, declarer surely did not have both a first round diamond and club control.

At the second trick East cashed the heart ace, on which West signaled helpfully with the diamond nine. Now East knew which suit to play, but were two diamond tricks standing up? When East took his diamond king, West followed with the six, count, to suggest an even number of cards left. That directed East to play a third heart. South ruffed with the trump jack and West overruffed with the queen. Note: if East doesn’t cash his diamond king before attempting to give his partner a heart ruff, declarer simply discards his diamond.

The expert declarer knows the percentages but may prefer to rely on deception rather than making the apparent percentage play. Let's look at a single-dummy problem — just the North and South cards.

Declaring four hearts In an unopposed sequence you are treated to a fourth highest spade four lead. The natural play is to put in the jack and hope the queen is onside; if not, you have virtually no practical chances of finding a 10th trick.

The psychologist plays low from dummy at trick one. East, holding A-Q-9-2 of spades can’t be sure if the lead is from two, three four or even five cards, and will surely not risk putting in the nine and having it lose to the 10 — that might lose at least two spade tricks on a particularly bad day, should South’s spade losers be about to vanish on a club or a diamond. Once the spade queen goes in, you can build a spade trick for a minor-suit discard. And if worst comes to worst, and East does insert the spade nine, you still have time to play a spade to the jack and enjoy your legitimate 50 percent chance, do you not?

The key to making these plays at a suit contract is to appreciate that you can virtually ignore the possibility of West’s underleading an ace at trick one against a trump contract; however, after the first trick, all bets are off.

Sometimes you have to take a chance to compete effectively. West's three diamond bid is risky, with no guarantee of a fit, but the aces and trump intermediates offer some protection from a double. North's final call is a difficult decision: He has trump tricks but no aces. Indeed, even after we see the full deal it is hard to tell how East-West would have fared in three hearts doubled.

After leading the club ace, West can see that dummy’s hearts and clubs will eventually provide discards for declarer’s diamond losers. No special measures are necessary if East has the spade king or diamond king. But if East’s only significant value is the diamond queen, more work is needed. Passive defense will not suffice: West must try to find a way to put East on lead to give a club ruff. Leading out the diamond ace would fail, because East will never get on lead, so a low diamond is the best chance. If East has the diamond king, the defense can cash out.

If declarer wins the diamond shift, West can learn that East doesn’t have the spade king by taking the second round of that suit and underleading his diamond ace again to get East on lead for a club ruff.

Of course, South can make West’s task just a little harder by putting up the diamond jack at trick two, but West should risk investing an overtrick by underleading his diamonds a second time, whatever declarer does.

When North set spades as trump after South had shown 12-14 points and a balanced hand, South had enough to show slam-suitability with a cuebid of four diamonds. That was enough for North, who checked on aces using Keycard Blackwood and drove to slam after hearing the response of two aces and the trump queen.

Slam would have been excellent on any lead but a diamond; however, that was West’s natural lead. South ducked the diamond king and won the continuation of the diamond jack with the ace. He then ruffed a diamond high in dummy, cashed the club ace-king, and ran all the trumps.

This is an example of a Vienna Coup, since it transfers the club menace to the South hand, and produces a three-card ending where declarer has three hearts in dummy and two hearts and the club jack in hand. As the last trump is led out East has to discard a small heart, and declarer now has to guess from the demeanor of the various players at the table whether East has come down to the doubleton heart 10, or Q-10 doubleton. If the former South must run the heart jack; if the latter, South must play hearts from the top and the nine will be good at trick 12.

There is no correct way to play the hand; South must gauge from the players’ demeanor at the table and the ease with which they make discards how likely one position is compared to the other.

If South had planned ahead properly, he might have brought home his contact of three no-trumps here. When West led the spade seven, dummy played low and East allowed South to win the trick with the jack. Now the contact was destined to fail. Declarer tried to sneak an entry to dummy in order to take the club finesse by leading the heart jack. But West was on the ball and hopped up smartly with the ace to play his spade back, allowing East to run the suit for down one.

By contrast, try the effect of playing dummy’s spade 10 at trick one. If East ducks, declarer is in dummy and can take an immediate club finesse. And if East cashes his top spades South has little choice but to play West for the heart ace, hoping East has no further entry to his hand. That way, South can engineer an entry to dummy with the heart king for the club finesse. When in dummy, he can afford to play East for king-third in clubs by leading the club 10, thereby blocking the suit, since four club tricks will suffice.

Should East allow the spade 10 to hold at trick one, South must play East specifically for the singleton or doubleton club king by leading low from dummy and finessing the queen then cashing the ace, thereby leaving an entry to dummy with the club 10. If clubs behave, declarer unblocks his diamond honors and runs dummy’s club and diamond winners for nine tricks.

On today's deal South's four diamonds set diamonds as trump and was virtually forcing. When North cooperated with what South read as a cuebid, South optimistically used Blackwood and drove to slam. West led a top spade and received count in the suit from his partner, then intelligently switched to a trump to kill one of the ruffs. As declarer you may care to take over after this start and plan the play to develop 12 tricks.

Good technique should see a double squeeze develop. The critical element of the play is that you need to make sure that only one defender can guard each black suit. You must win the trump in dummy and ruff a spade, then cash the club ace and king and ruff a club with dummy’s last trump. Now ruff a spade back to hand, isolating the spade menace with West, and run all your trumps. When you play your last trump, one opponent is guarding spades, and one opponent is guarding clubs. In the two-card ending West pitches down to a bare heart honor to preserve his spade winner, and you now pitch the spade from dummy to squeeze East in hearts and clubs. If he lets a club go, you cash your club six; if he pitches a heart dummy’s heart jack will take trick 13.

Just for the record, had West worked out to lead a trump initially, the defenders would have prevailed. After the actual first trick, there was no defense to the slam.

You will be faced with a series of problems as East today. After the auction starts with South opening one diamond and North responding one heart, there are many players who would feel obligated to act. But despite your quick tricks, you have sterile distribution and no reason not to assume that you are outgunned on the deal.

So you pass, perhaps planning to re-enter the auction if the opportunity presents itself. Instead, you hear South jump to two no-trumps and North raise to game. Your partner leads the spade seven. You play fourth highest leads, but also second from four small and you may also lead top of three small. Declarer plays low from dummy and it is up to you to decide what to do now, and how to plan the defense.

Partner has almost a bust — but there is just about room for him to hold a heart honor such as the queen. Your best chance is to try to deny dummy an entry, so play the spade nine at trick one. Declarer can still succeed by playing on hearts, since the spades are blocked. But he does not know that.

Since he cannot see through the cards, he is likely to try to get to dummy with the club queen in order to take a diamond finesse. If you can stop him from doing this by winning the club ace and clearing the spades, then shifting to hearts, you will defeat three no-trumps.