[LashOut]

Hi, I noticed that neither did East lead diamond A nor lead heart Q when I read the solution carefully.

So, why does East open like this?

[smerriman]

I don't understand your question - West led, not East, and in the main line, chose from T from T987, so no underleading involved. It would be rare to lead an unsupported Ace. Are you referring to some other play later on?

[LashOut]

smerriman, on 2025-December-02, 20:53, said:

I don't understand your question - West led, not East, and in the main line, chose from T from T987, so no underleading involved. It would be rare to lead an unsupported Ace. Are you referring to some other play later on?

Sorry I mistyped (Yes, I was actually thinking about another play when typing East...).

But the solution says "West's ♥10 might be from an interior sequence headed by the ♥Q" so why should West lead heart T instead of heart Q in that case?

Also, how does West know diamond Ace are not supportive?

[LashOut]

smerriman, on 2025-December-02, 20:53, said:

I don't understand your question - West led, not East, and in the main line, chose from T from T987, so no underleading involved. It would be rare to lead an unsupported Ace. Are you referring to some other play later on?

I'm just a green hand and have an ocean of questions. Thanks in advance

[smerriman]

There are different lead conventions that people play, but "standard" is that if you lead an honor, it should promise the one directly below as well (other than in rare cases like leading from shortness). This is both to avoid giving away a trick cheaply (if declarer wins and holds the next lower card themselves, which you would have been able to cover otherwise), but also to help partner know more about your hand so they can have a better idea how to play themselves. Without a sequence, you should lead low and hope partner has an honor to play instead.

Ace is an exception - if you had to lead from a suit containing just an ace, while the ace lead isn't great (might give away a trick to the king), it's virtually never correct to underlead it, since not only might that give away a trick, but you might never take the ace at all later if declarer has a singleton or discards their remaining cards in that suit on other winners. So normally you'd look to lead another suit, but if you had to, you'd lead the ace.

But with this hand whether West has the diamond ace isn't important; when they lead the ♥T you know they definitely don't have the ♥A. It's probably unlikely they have the ♥Q either, but it's not impossible, so at least playing the J has a small chance of gaining you an extra trick.