This deal is from the Great Northern Swiss Pairs held in Leeds earlier this month. North South were England internationals Helen Erichsen and Fiona Brown.
Helen Erichsen sitting North faced a difficult decision at her second call. If there were nine running tricks, then three notrump was likely to be the best contract, otherwise three notrump would probably go off. She did well to bid four clubs, which was a bit murky as to its meaning, but they safely stopped in five diamonds.
On a spade lead Fiona won, knocked out the ace of diamonds, and won the diamond return. She now had eleven tricks, but had a chance to make twelve if she could bring in the heart suit for no losers. West was likely to be short in hearts so she had to find him with 10x or 87 doubleton. She played the heart queen from table covered by the king and ace, West following with the eight. It is now a restricted choice position, West is as likely to have been dealt 108 or 87 doubleton, but if he held the latter he would play the eight about half the time. So she played the jack in attempt to drop the ten - right in theory, wrong in practice, running the nine would have been successful. Playing in five diamonds earned them over 90 percent on the board anyway.