Wainfleet, on 2020-July-27, 00:06, said:
My partner and I have had it drummed into is that you never lead away from an ace in a suit contract, and you very rarely lead an unsupported ace. In an Advanced level bridgecast from Andrew Robson last week the auction went 1
♥ - (1
♠)- 3
♥ - (3
♠) - 4
♥ - all pass.
Opening leader had:
The commentary was "When you are leading your side's bid and supported suit you lead the ace rather than a 'low card"
This was a new one on me. In this auction the defenders have at least 9 spades so the odds are that spades will only run once without being ruffed. But what if advancer had bid 2
♠ rather than 3
♠. Would it still be right to lead the
♠A rather than a small diamond, which I don't think is a good lead either.
Elsewhere Robson says that it can be right to do so vs a slam, particularly at pairs where there is a risk that if you don't take the ace at the off you might never win with it and the overtrick can be important.
Other references say that you should only do so when all other options are worse.
Selecting an opening lead against suit contracts can be difficult, to be sure. You basically have to figure out what declarer's plan will be and then try to counteract it.
1. If you think declarer will try to set up a long suit in dummy (maybe dummy opened 1H, the opponents reached 4S, and you have Qxx of H under dummy), consider an attacking lead.
2. If you think declarer will try to ruff losers in the dummy (maybe dummy is marked with shortness in a suit where you have strength), consider a trump lead.
3. If you think dummy will be flat (no ruffs, no long suit), then consider a safe lead. Declarer will probably try to set up tricks by finesses, so you don't want to give him anything he isn't entitled to.
Generally, you only make a lead from category 1 or 2 if you know what the situation is. If there are no clues, then you just pick a safe lead, especially at MPs.
Generally, leading from longer suits is much safer than leading from shorter ones (if you lead from QTxxx and partner doesn't have anything, there is a decent chance that declarer could have ruffed the third round anyway; if you lead from QTx and partner has nothing, you probably have just kicked a trick). Leading from shorter suits headed by an honor is more attacking.
OK, so how does this translate to the hand you provided? We don't know a lot about the opponents' hands from the bidding. Dummy isn't marked with any shortness or long side suit. So we need to make a safe lead. Nothing is entirely safe here:
1. The As will boot a trick if declarer has Kx(x) and partner has QJx(x) or QTx(x) with xx(x) or Jx(x) in dummy.
2. The trump could solve declarer's problem if partner has Qxx or Kxx.
3. A diamond will often give a trick if partner has the unsupported A or K.
4. The club is obviously very dangerous.
To me, the logical lead is the As. Partner supported, so there is an excellent chance he has the K. If he doesn't, the King could well be in dummy (dummy is likely longer in spades than declarer, since it probably has fewer hearts). That might end up not costing a trick. Moreover, leading the As gives you a chance to get a peek at the dummy and a signal from partner as to what to do next.
This is very different from leading a random Ace in a suit your side hasn't bid. That is more dangerous, especially when you don't have great length, because you will often be setting up tricks for the opponents.
Leading against suit slams is a different story. Typically, the dummy in a suit slam will have a side source of tricks (a long suit that can be developed). Especially at MPs (but to an extent, in IMPs, too), if you have a side A, you generally should take it. If you don't take it, you may never get it (declarer will have enough discards on dummy's long suit). In addition, your best chance to defeat the slam could be that partner has a singleton in that suit or perhaps the King (if the opponents haven't been careful in their bidding).
Cheers,
Mike
+++++++++++++++++++++
When partner has raised ♠ to the 2 or 3 level, I rank
1. ♠A. In case declarer can discard losing ♠s. Definitely lead this against a slam
2. ♥2 = Probably safe.
3. ♦2 = Agree with Wainfleet that this isn't necessarily safe..
4. ♦J = Not necessarily safe either.
5. ♣K = Ultra-aggressive.