IBPA Column Service example 862
Dealer South. Both Vul.
 K J 10 8 4  J 7  4  9 8 5 4 3 |
||
 6 3 2  K Q 9 8  Q 8 6 2  K 2 |
 —  10 6 3  K J 7 5 3  Q J 10 7 6 |
|
 A Q 9 7 5  A 5 4 2  A 10 9  A |
The Auction:
West | North | East | South |
1 | |||
Pass | 4 | Pass | 6 |
Pass | Pass | Pass |
West led a low trump and declarer won the trick cheaply in hand. Declarer could count eight top tricks. However, as there were not the entries to set up clubs and enjoy the established winner, declarer saw that he needed to ruff four cards in dummy to make his contract.
So, West was the danger hand, as he could lead a second trump to scupper the contract. One potential winning position was when East started with both the king and queen of hearts; the contract would then make unless there was a distributional nightmare in the side suits.
However, as the chance of that occurring was well below even money, declarer decided to try his luck in diamonds first. At trick two he cashed the ace of diamonds and continued with a tricky nine of diamonds, intending to throw a heart from dummy if West followed low.
When West played the queen of diamonds declarer had to ruff in dummy. After cashing the ace of hearts and the ace of clubs, declarer led the ten of diamonds.
West had to follow with a low card and declarer discarded dummy’s jack of hearts. East took the trick with the jack but declarer had the last seven tricks on a high cross-ruff.
If West had covered the ten of diamonds, declarer would ruff then hope for the best in hearts. Essentially, declarer would have made his contract most of the time that East had at least two diamond honours or the king and queen of hearts, which totals to about 70% of the time, assuming that West would have led a diamond if he’d held the king-queen-jack.