BBO Discussion Forums: Defensive Problem - BBO Discussion Forums

Matchpoints. South leads the J♦. From the afternoon pairs at Brighton this Monday. Plan the defence.

Disappointed that nobody is having a stab at this. It is a theme I have not seen before, and I think can be worked out at the table, and the defence would be the same at teams.

Honestly, it took me like 3 minutes just to figure out who's dummy and declarer. Someone please tweak the script.. it's might annoying for defensive problems.

As to the play, I can see three possible lines. Take ace and:

1. Trump, hoping pard can play a couple more before declarer gets enough ruffs.

2. Underlead club king, playing partner for Ax. Not too much of a prayer, but it's risky and pard might have tried the ace for opening lead with the doubleton Ax.

3. Small heart, playing pard for a singleton, trump stop and club ace. But again, pard might have led that singleton.

I though if ducking the ace could achieve something, but I couldn't figure anything out. I would probably end up just playing a trump.

whereagles, on 2014-August-13, 04:29, said:

I think one is restricted by the software to present them this way, sorry.

I know. Users can't fix it, of course.

Point is, lack of clarity is probably one of the main reasons defensive problems get less attention.

whereagles, on 2014-August-13, 04:29, said:

I see 2 more possible lines:
4. Take ace and return a passive ♦ - quite boring I know
5. Duck the ♦ - no idea why this would do us any good, so I guess that's what we have to do

I guess I'm quite boring

I'm not seeing it. Probably the remaining points are divided something like 16-6 or 17-5 between declarer and partner so pard probably has something like Axx xx J10xxxx 10x and declarer KQJ10xx AK xx Axx. Looks like we can't get any more than three tricks. Even if partner has a singleton heart (and for some reason not led it), then we can't ever get in to give him the ruff.

ahydra

I would duck at trick 1. This could look silly if partner has seven diamonds, but with that type of hand there's a fair chance that partner would have bid 4♦ after my double or (if that is his style) made a 3♦ weak jump overcall.

My reasons for ducking are:

1. I don't know what to play back at trick 2. I'll have more information from declarer's line of play and/or partner's signals when (I'm hoping when rather than if!) I get in with ♦A later on.

2. It could be technically necessary to deny dummy an entry later in the play. Suppose declarer has ♣A10x or A9x and partner has a trump trick (♠Kxx or Qxxx). He would like to draw trumps, then take the club finesse. If we force him to use his entry to dummy a trick 1, he may choose to take two ♣ finesses immediately but then partner can ruff the 3rd round of the suit and ♦A is my entry to give him that ruff.

It is just possible that partner has Ax in clubs but it would require that declarer has 4 small cards in the minors, which must be unlikely given his strong bidding.
At IMPs I might play for that but not at matchpoints where every trick counts.
Partner is weak and has preempted vulnerable with a suit headed by the jack opposite a limited hand.
I am inclined to play him for a seven card diamond suit, in which case ducking is a bad idea and dummy has no quick entry. So returning a diamond looks wrong to me.
It is also clear partner does not have a singleton heart or he would have led it from his weak hand.
It follows he is either void in hearts or has at least two hearts, in which case a heart must be quite safe and could easily gain.
So return the ♥5.
Even in the unlikely case that partner has the ♥A and declarer the ♥king declarer should not guess right.
But since partner has some cards in spades it seems more likely that partner has a void in hearts, will ruff and will hopefully play back a spade and keep declarer out of dummy.

For example



If partner ruffs and returns a low trump we might actually beat this contract.

Rainer Herrmann

This hand shows one reason why partner should make a count lead at trick 1. He knows you have at least 9, possibly 10 diamonds between the hands, why bother leading the jack?

non expert answer I will return low h and not play pard for Ax in clubs.

why?

I attack clubs or hearts and hearts is the weaker suit.

jallerton, on 2014-August-13, 13:02, said:

Your instincts are correct and it is indeed necessary to duck the first trick. The full layout:

If you win and return a diamond, declarer can run the jack of clubs, cash a high spade and the two top hearts (a Dentist coup), and exit with a low spade and South is endplayed. After you duck the diamond, the most testing line is to run the queen of clubs, cash one top spade and both hearts and exit with a diamond. The defence can still prevail as North leads the queen of hearts and South declines to overruff! Frances' point about a count lead is a good one, and most strong Swedes were playing 3rd and 5th leads when I played against them. It seems, however, that North cannot tell at trick one whether South has six or seven, unless NS has agreed to lead seventh when one has seven, an agreement I have never seen, and one that would be improbable in an Open Pairs at Brighton with a pick-up partner. At least South found the diamond lead, when the singleton club would have failed.

My last sentence above shows my lack of understanding of 3rd and 5th leads, as I believe one should lead 3rd from six and 5th from seven. With that agreement, North can tell, and should find the duck.

This post has been edited by lamford: 2014-August-14, 04:21

The original "odd leads" idea is

Smallest from an odd number of cards
3rd from an even number of cards (top if doubleton)

xx
xxx
xxxx
xxxxx
xxxxxx
xxxxxxx
xxxxxxxx

Follow-up card is also defined. I think it's something like (can't recall by heart, so might be a bit off)

xxx: 3rd, then 2nd
xxxx: 3rd, then 4th
xxxxx: 5th, then 1st if possible
xxxxxx: 3rd, then 2nd if possible, smallest otherwise

As to the hand: neat idea. Forces declarer to make a decision at trick 1. Declarer should probably get it right and opt for the club finesse (doubler rates not to have spade queen), but he might go wrong.

whereagles, on 2014-August-14, 05:05, said:

Thanks for the clarification on 3rd and 5th leads. On the hand itself, after the diamond is ducked, declarer has no way home. The defence might still go wrong.

Make sure pard plays odd leads as you do (this is not a trivial issue). I once blew 12 imps because my pard randomly played 3rd or 5th from 6 cards and I didn't know what to do.

FrancesHinden, on 2014-August-13, 16:11, said:

I think your point is more valid when the opening leader has a 7-card suit.

If the opening leader has a 6-card suit:

(i) It could be right to attempt to hold the lead. Suppose that dummy has ♦Kxx and declarer a singleton. A forcing defence may be best.

(ii) Dummy could have Qx opposite declarer's A9. Leading low is a bad idea double dummy, although in practice declarer is likely to play the Q at trick 1 anyway, I admit.

(iii) On some hands, denying the Q at trick 1 is useful information to partner.

lamford, on 2014-August-14, 04:07, said:

Yes, South did well, but I suspect he might have been more tempted to lead his singleton with ♠Qxxx rather than ♠Q108x. That's why my hand contruction gave him a doubleton club.

FrancesHinden, on 2014-August-13, 16:11, said:

Even playing count leads partner would find it hard to convince me that he had seven diamonds. Didn't I make a takeout double of spades at some point?

gnasher, on 2014-August-14, 15:36, said:

It was North who made the takeout double of spades. Didn't Vampyr return your spectacles which you left at our barbeque?

lamford, on 2014-August-17, 04:25, said:

Aren't I North?