We took part some days ago in an ACBL BBO Tournament with Tom Szabo, a student of mine. We got this very interesting problem in a pairs tournament, where every point counts.
Leet's see, what had happened?
The opening lead is not so easy. Every suit, including the nine of spades is possible, and every one is dangerous.
The nine of hearts is a normal lead, but a very bad one, you have good cards in spades, so you don't want to make a ruff, and heart honours seem to be at your partner and at declarer, so this lead can help a lot for the declarer.
Diamond lead is neutral, but dangerous, because declarer seems to be very strong.
Trump lead can be good if declarer has 2 shourt suits and you can avoid a ruff in the dummy, but you are sitting behind the declarer, so yoou like to put trumps after the declarer, and you have controls in every suit to play spade later if it is necessary.
So we arrived at the Ace of clubs lead. We don't have honor and medium size club, so we cannot make a finesse in this suit, so we can lead the Ace of clubs easier, as usually.
On the other hand, if we start with the Ace of clubs, we most probably win this trick, and we can continue better, if we can see the dummy, and the partner's signal.
And if the declarer can be tapped, the Ace of clubs gives us the best chance to start it.
So I led the Ace of clubs, and the following cards came to the dummy:
Tom put the six of clubs, and the declare the Queen, so declarer seemed to have singleton Queen fo clubs.
Heart is still not good, club is terrible, and we have seven of spades in our hand, what means, that we can ruff the 3rd round of hearts not allowing ruff in the dummy.
Therefore our smallest diamond is the right card now. Really big truble comes only if declarer has Ace and Queen only, but if out guess is right about his singleton Queen of clubs, it isn't so feasible. And one thing is sure, the diamond continue isn't trickable at the dummy.
So I played the five of diamonds, dummy played small, Top put the 2 and declarer won it with the Queen. It is a very smart card, but our partner cannot have the Jack, so Tom has most probably singleton diamond.
Declarer now cashed his Ace of hearts, his King of hearts, and he tried to ruff a heart in the dummy, but I coud ruff it with the seven of spades, I played a diamond, which was ruffed by the partner, he played another heart, which I could ruff, and I played my last diamond, what was ruffed by Tom.
We came to this end-play situation, collecting 5 tricks already:
Tom played his last heart, and declarer had no right choice.
If he ruffs with small trump, I can overruff him with the ten.
If he ruffs with the Jack of spades, (as he did), we should simply duck it, so he has to play from K843 of trumps, when I still have Ace and Ten in spades, and Tom has the singleton Queen, securing 2 spade tricks for us, finessing declarer's King.
50 points only, but great score in a pairs tournament.
The complete distribution was: