San Remo, 2009, the final of the Open European Championship. Team 'Netherlands White' (Sjoert Brink - Bas Drijver and Bauke Muller - Simon de Wijs) plays Israeli team Herbst.
A brilliant manoeuvre by Ilan Herbst gains his team 10 IMPs.

E/All		♠	J 9 6 3
		♥	Q 10 8 7
		♦	9 5
		♣	A J 2
♠	-			♠	K 10 8 7
♥	A 5 4 3 2			♥	K J 6
♦	K 8 7			♦	4 3
♣	K 8 6 5 4			♣	10 9 7 3
		♠	A Q 5 4 2
		♥	9
		♦	A Q J 10 6 2
		♣	Q

¹ at least 5-5 in hearts and clubs

Barel leads the ♥A and continues the suit, declarer ruffing. Brink lays down the ♠A and it becomes clear he will have to lose two trump tricks. West might have bid 2NT even without the ♦K, so East might have that card (although West is more likely to have it). In the end Brink finesses in diamonds and ends up one down.

At the other table West, De Wijs, overcalls 1♥, not 2NT:

De Wijs leads a small heart to East's ♥J. Muller returns the ♥6, South ruffs.
Here too the declarer lays down the ♠A, noting he has two trump tricks to lose. He notes too that West has only one top honour in heart (although Herbst probably will think this to be the ♥K rather than the ♥A...).
Herbst realises East has not made a cue bid (bid in the opponents' suit; a cue bid after partner's overcall shows a good raise in his suit). East just gave a simple raise... Since he has shown up with ♥A(!)Jx and ♠K1087, East cannot have the ♦K as well.
So Herbst continues with an innocent looking small diamond from hand! Very daring, since he will have some explaining to do if East would turn up with the ♦K after all! (East might have thought that card useless, before the 1♦ opener).
De Wijs eyes South's small diamond with suspicion. He doesn't know that playing the ♦K is enough to defeat the contract (although... see P.S.). In the end he plays a small diamond. Dummy's ♦9 wins the trick. Declarer now crosses to the ♦A and ruffs a diamond.
After that he only loses the obvious two trump tricks (although East can shorten South's trump suit, but that does not embarrass declarer; just play). +420 and +10 IMPs to the Israeli team.

It is not enough though: Netherlands win the final by a small margin.

P.S. As so often there is yet an indication for West that he should have gone up with the ♦K: in view of the bidding it is very likely South has five spades at most, six is hard to imagine after a 1♦ opening. So East has four. Now look at East's card on the ♠A: the ♠7. If that is indeed his lowest spade (and why would he mislead his partner?), he must have two sure spade tricks!