This deal was published last year in the Goren Bridge column:

Vul:N-S Dlr: South	K983  J104  A76  AK2
AQ54  853  KQJ10  86		1076  7  95432  J1043
	J2  AKQ962  8  Q975

South opened 1 and West made a takeout double (not my choice). After some optimistic bidding, North-South reached 6 with the obvious K lead. Clubs aren't 3-3 and declarer can't ruff a club in dummy on this layout. The analysis focused on the spade suit.

Declarer won the A and crossed to the A to lead a low spade. West could (should?) have played second-hand low. Instead, he took his ace and look what happened next. He exited with a diamond, ruffed by declarer. The J was led and West had to cover. Later, the 10 fell and dummy had a good spade for declarer's 4th club. Had West ducked the A, declarer could no longer set up a spade trick--down one. Or so the newspaper said.

Is it down one? My take on the deal is that the spade suit (aside from the need for West to hold the A) didn't matter. Declarer should win the A and trump a diamond at trick two. Now on the spade play, let's say West correctly plays low. Declarer can still make the contract! He wins the K, trumps dummy's last diamond and gives up a spade. The best West can do is exit in clubs or trumps. No matter. The stage is set for a dummy reversal.

Declarer can win the return in dummy and trump a spade high. He crosses to dummy again and trumps the last spade high. He then draws trump ending in dummy. In effect, declarer's fourth club is thrown on dummy's third trump. Declarer takes 3 clubs 1 spade, 1 diamond, 4 ruffs in hand and then draws 3 rounds of trump. Try it!

Note: Only a club lead (not likely) would set the contract.