The intrafinesse is one of the more obscure bridge plays and comes in all shapes and sizes. Often the problem is simply determining whether to go for the play, or to rely on something else.

Here, at matchpoints, Kit Woolsey as South reached four no-trump. On a heart lead declarer required the clubs to lie in a very specific fashion in order for them to produce three tricks. He needed the doubleton 10 sitting over him or to for East to hold a doubleton king-queen or bare honor.

However, the key to the hand is to avoid committing yourself at once, but to win the heart ace, and take two top diamonds, at which point you find East with shortage. On that basis you should play West for short clubs, namely the club Q-10 or K-10. What you do is lead up to the club jack, varying your play according to what West does. If (as happened at the table) he puts up his honor and clears the hearts, go to dummy in diamonds and play the club jack to squash the 10. When the cards lay exactly as Woolsey required them to do, he racked up plus 430 for a fine result, since the heart sacrifice costs only 300.

West could have left declarer with work to do had he put in the club 10 on the first round of the suit. Then Woolsey would have had to decide whether West had a singleton10, a doubleton 10, or his actual holding.

Today's three-no-trump deal was too difficult for all the players at the table. But will you, as West, be able to solve the puzzle?

Declarer won the spade lead in dummy, East following with the six to suggest an even number of spades. Now, instead of going after clubs, declarer (who had begun with the doubleton heart king) played four rounds of hearts, pitching clubs from hand as East discarded the two then four of spades.

Can you work out what is going on — and what the killing defense is now?

You should have built up a picture of East’s hand as four small spades and two hearts, together with three diamonds and four clubs. His failure to discard a discouraging diamond marks him with an honor. Logic suggests that he has queen-third of diamonds or else he would surely have kept two spades, rather than break the partnership communication in that suit.

The winning defense is to take the spade ace now, then exit with the club queen, hoping partner has as little as 10-fourth of that suit. Declarer can do no better than win the club and hope to split the suit. When East takes his two club winners, you will discard a spade, then a diamond, and — to add insult to injury — the last club squeezes dummy! Declarer will end up with just seven tricks.

Yes, declarer should have played on clubs not hearts, but that is no reason to give him back his contract.

In 2007 the trials were held to determine the second USA Open Teams spot, and the squads captained by Seymon Deutsch and Rose Meltzer met in the quarter-finals. On the deal that followed, Bart Bramley and Sidney Lazard for the Deutsch team came off better.

Bramley and Lazard are one of the few pairs who have stuck with a version of Standard American more common in the 60s and 70s; but they have no shortage of inspiration in both the bidding and the play. Against three no-trump, Bramley led the spade two (standard fourth-highest leads) and Lazard played the spade king, which held. West’s lead, coupled with the bidding, suggested that South held four cards in each major, and dummy’s diamond suit looked likely to provide six tricks.

Any guesses as to which card Lazard played back at trick two? Yes, it was a club — but which? He chose the king, and when that held, followed up with the club eight. To declarer, it appeared that for his club-king switch, East must also hold the ace. So she rose with her queen, and now the game ended two light, courtesy of four club tricks plus the two top spades.

Lazard’s play could hardly cost. With any needed finesse in the red suits working for declarer, a shift to clubs might cost overtricks, but it was virtually impossible for it to cost the contract.

Four hearts appears to be a simple enough contract, but as always, you need to make the right plan at the start of the play. You should aim to score five trumps, four clubs and the spade ace.

You will need to ruff the clubs good if they divide 4-2, which is the most likely split.

After establishing the clubs, you will have to draw trumps, ending in the dummy.

It follows that you should not aim to take a spade ruff. (That would be so even if West had not bid, thereby alerting you to the risk of an overruff by East.)

How does the play go? Best is to win the spade lead (for fear of a diamond switch) and draw just two rounds of trumps with the ace and king. You then play the club queen and ace and ruff a club in the South hand. This line would cost you an overtrick if clubs happened to break 3-3. But it is in a good cause, though, because you give yourself an extra chance when clubs break 4-2. Here West is out of clubs, but cannot overruff.

You return to dummy with a trump to the queen and score two more club tricks.

The trap on the deal would be to start by drawing trumps. After that start you would make the contract only if clubs broke 3-3 or the diamond ace was with West.

Incidentally, if trumps broke 4-1, you would just run the clubs, pitching spades, and hope for the best.

Regular partnerships have firm agreements about leading honors against no-trump. One of the more sensible agreements is that from ace-king combinations, you lead the king if you want your partner to unblock the queen or jack, while the ace asks for attitude. Under the king, third hand drops an honor if he has one, or signals count.

Today, against three no-trump West leads the heart king and East follows with the 10, suggesting a four-card suit. Now West knows a heart continuation would set up South’s queen, so he shifts to a club. Declarer wins the king and has to find a way to a ninth trick.

While declarer could hope to develop a trick from the spades, diamonds offer far more hope. At trick three, declarer must lead the diamond eight from the board, as a sort of avoidance play. He is trying to set up a diamond trick while keeping East off lead. This approach will produce two tricks when East has only one of the diamond 10, queen or king.

Here West wins the diamond and plays a spade. South wins in hand, leads a club to the board, then plays the diamond jack, intending to let that card run if East plays low. When East covers, declarer wins the ace and plays a third diamond, thus setting up the long diamond for his ninth winner.

It happens more often than it should that declarer falls at the first hurdle – by miscalculating whether to duck or win the trick. Today, when West leads the spade six against three no-trump, East covers the 10 with the jack. How do you plan to make nine tricks?

If you let the spade jack hold, East will shift to the heart queen very smartly and, as he has two entries to his heart suit, you will lose a spade, three hearts, a diamond and a club for down two.

So you must win the first trick and then decide which minor suit to play next. I hope you will see that you should play on diamonds next, because tackling clubs first would see you lose the contract whenever West began with five spades, as well as the diamond ace, and East started with the club king.

So you should lead the diamond king next. East wins his diamond ace and exits with a spade. Only now do you duck the spade, severing the link in spades between the defenders’ hands.

You will win the next trick in hand and take the club finesse by running the club nine. East will win the king and will have no spade to play. So you will make two tricks in each of spades, hearts and diamonds, plus three in clubs.

Note that even if East did have a spade to play, you would still take nine tricks as long as spades were originally 4-4.

In today's deal South might have looked for a slam after the two-no-trump rebid. Over the forcing rebid of three spades, North can cooperate with slam interest or sign off in no-trump or spades with a minimum in context.

As it was, though, it was just as well that South restrained himself, because even 10 tricks proved quite difficult to accumulate. West led the heart queen and declarer rightly refused to play dummy’s king on the first two rounds. (If West held Q-J-10-x-x, East’s ace would appear on the second round and dummy’s king would be worth a trick.)

But how would you continue the play when the defenders take three heart tricks and East then switches to a club? You win in dummy and run the trump nine successfully. When you lead dummy’s last trump and finesse the queen, West shows out. What now? You must aim for a trump-coup end-position where you hold A-J of trumps in your hand and the lead is in dummy. Because of the shortage of entries to dummy, you must cross your fingers and lead a diamond to the 10, ruff a club, re-enter dummy with the diamond queen, and ruff another club. When you cross to dummy’s diamond ace East follows suit, and you have reached the required two-card end position. Your A-J of trumps sit over East’s K-8 and the lead is in dummy. You can play a club and take the rest whatever East does.

In today's deal West knew that his opponents were in a thin three-no-trump contract (East had to have a few points for his voluntary heart bid) and so was reluctant to lead a heart, which could easily have given declarer a trick. Instead, he chose what he hoped was a passive diamond, and in a way he was right because the diamond did not give anything away.

Declarer won in hand with the queen, played a club to dummy’s jack and East’s 10, then led a club back to his queen, East following with the 10 and the nine, West winning his king.

West now switched to the heart queen, which held the trick. What now? West continued with another heart, won by declarer’s ace, and declarer rattled off four more club tricks. At this stage declarer had seven tricks and needed two more. Everyone was reduced to four cards, and as dummy was discarding after West, there was an answer to anything the defense did. West’s best shot was to come down to three spades and a singleton diamond ace. But declarer simply kept two diamonds and two spades in dummy and led a diamond up.

When the heart queen held, what West needed to do was cash both his aces before he played another heart. Since East had given count in clubs and hearts, West might have been able to work out declarer’s shape. This defense forces declarer to give East a heart trick after he has cashed his clubs.