The Hand:
IMPs: Dealer East; N/S Vulnerable
 Q J 6 5 3 3 2  A K J  A K 9 |
||
| A K 10 4 2 A 8 7 3 J 8 4 3 |
The Auction:
| West | North | East | South |
| 2 |
2 |
||
| 4 |
5 |
Pass | 6 |
| Pass | Pass | End |
Final Contract: 6
Lead: 10
North’s jump to five spades asked South to bid six if he had a heart control.
While South did have a first round control in hearts, the fact that he was pretty much minimum for his overcall argued against a first round contol-bid of six hearts along the way to the spade slam.
West led the 10 to declarer’s ace. Declarer counted ten top tricks with an eleventh available from a heart ruff. The extra trick could come from the club suit or from a winning diamond finesse.
Clearly, the club suit should be tested first with the diamond finesse as a fallback. After drawing trumps with the ace and queen, declarer placed East with eight cards in the majors.
As a result, declarer rated the normal play in clubs of ace, king and another as too fragile an approach to the suit – it would lose when West started with queen-ten-to-four or -five. Also, when West did start with four or five clubs in length in the club suit, it became less likely that the secondary chance of a successful finesse in diamonds would succeed.
After some thought, declarer developed a plan that would always bring a twelfth trick as long as East started with six hearts. First, he cashed the ace of clubs, then ruffed dummy’s remaining heart. Next he led a low club towards dummy’s king-nine. When West followed with a low club, declarer called for dummy’s nine and, when that held, he had twelve tricks.
West suggested that this was a lucky play. Declarer retorted, “You should see that this plan succeeds against any club layout. If East takes the nine of clubs with the ten and the suit is 3-3, then dummy’s jack of diamonds can be discarded on the thirteenth club.
If you began with five or six clubs then this approach will always produce an extra trick in the suit. It also works when East takes the nine with the queen or a doubleton ten: in the latter case, East will be endplayed and forced to concede an extra trick either by leading a diamond into dummy’s tenace or to conceding a ruff-and-discard.
Finally, if East started with four clubs, then he could have at most one diamond; so, after cashing the ace of diamonds, finessing the jack of diamonds would produce a guaranteed twelfth trick.”