AN EXCERPT FROM The Golden Rules of Defence (and when to break them)

By Marc Smith & Julian Pottage

Rule One: Third Hand High

Third hand high' is one of the first rules bridge players learn. Indeed, the concept pre-dates bridge, and was used by good nineteenth century Whist players. Our first example shows why the idea is a crucial part of effective defence. Defending a no-trump contract, partner leads the five (fourth highest) of this suit:

	10 6 3
AJ952		K84
	Q7

Sitting East, if you play any card but the king then declarer will score a trick to which he has no right. Playing third hand high prevents declarer scoring a cheap trick.

Sometimes you cannot win the first round of the suit. Even so your high cards can force out declarer's stopper and build tricks for your side:

Game All

	A75
	Q4
	1084
	KQ963
Q108		42
A106		9752
Q765		K92
J72		A1084
	KJ963
	KJ83
	AJ3
	5

1	Pass	2	Pass
2	Pass	3	Pass
4

Partner leads the 5 of diamonds and dummy follows small. The opponents have AJ10 of diamonds, so declarer must score two tricks in the suit. Your task is to set up a cashing trick, and to do that you must play the king. When your side regains the lead partner will be able to cash the Queen of diamonds to go along with your three obvious winners -- one down!

If you do not play the king, declarer will lead a club and later discard his diamond loser on dummy's winner. Playing third hand high knocks out declarer's stop(s) and builds defensive tricks.

It may sound obvious, but a key aim when defending is to take tricks. Playing your highest card is the most likely way to achieve this objective. In the examples above, contributing your highest card in third seat met two goals -- you took (or set up) tricks for your side and prevented declarer from making cheap tricks. Sometimes, you can achieve only one of these goals:

	1052
K974		AJ3
	Q86

This is the heart suit. Partner leads the four against a 4 contract. From your hand and dummy's you can deduce the layout of this suit -- declarer has three hearts including either the king or queen (partner would have led an honour holding both). Are you tempted to put in the jack to force out declarer's honour?

Playing the jack in this situation is called 'finessing against partner'. Of course, if declarer's honour is the king, it will not matter what you do. However, playing the jack cannot gain a trick and often costs, as here. The third hand high rule tells you what to do -- play the ace. Although dummy's ten stops you cashing three winners in the suit, playing the ace avoids conceding a cheap trick. Here is another example of finessing against partner:

	K8 3
J7652		Q94
	A10

Partner leads the five and dummy plays small. If declarer has A-J or partner has J-10, then it matters not whether you play the queen or nine.

Only when the layout is like that shown will your play affect the result -- playing the queen limits declarer to two tricks whereas inserting the nine lets him score a third. The play of the nine cannot gain, but it can lose. So, how do you know whether to play the queen or the nine? Playing third hand high avoids finessing against partner.

In these two layouts, playing third hand high was correct because your two highest cards were equals against dummy. In one case you had A-J and dummy the ten, and in the other your Q-9 were equals against dummy's K-8. You had no tenace over RHO (right-hand opponent) and thus playing your second highest card would have been finessing against partner. Now consider these layouts:

	K104
J865		Q93
	A72

Now your Q-9 surrounds dummy's ten. When partner leads the five and dummy follows small, inserting the nine forces the ace. Against a suit contract (when partner is unlikely to have underled the ace) this action cannot cost. When declarer has A-J your play does not matter. If you play the queen here, then declarer could later finesse partner's jack and make three tricks in the suit.

	Q72
J963		A104
	K85

Once again, dummy has a card (the queen) that ranks between your two highest cards. Partner leads the three and if you play third hand high (the ace) then declarer makes two tricks in the suit. However, if you insert the ten (to finesse against dummy's queen), he can score only the king. Defending against a no-trump contract, playing the ten cannot cost. Should declarer have the jack rather than the king, then he would still only make the one trick due to him. Not playing third hand high gains when you hold a tenace over RHO.

Of course, winning a specific trick is not your sole aim in defense. As we shall see, there are times when other factors must take priority.

Dealer South

	K7
	Q106
	Q105
	K9643
10852		J94
J854		K732
A862		974
2		AQ7
	AQ63
	A9
	KJ3
	J1085

1	Pass	3	Pass
3NT

Partner leads the 4 of hearts and declarer plays the six from dummy. Do you see what happens if you blindly follow the third hand high rule and play the king? Declarer will win the ace and play on clubs. Whatever you do next, he can establish enough minor suit tricks to make his contract.

Note the difference if you withhold your king at trick one. Let's say he now finesses the jack of clubs to your queen. You then play a second heart to the ace. Declarer next plays a club to your ace but you can now cash the King of hearts and lead a fourth heart to partner's Jack. The ace of diamonds will be the fifth defensive trick -- one down!

Can this third hand play cost?

No. If partner had the ace (or even A-J), then dummy's Q-10 would ensure that declarer always has one stopper. The only difference is that ducking would give declarer his heart trick on the first round. If partner started with Axxx of hearts, he would win the second round and you could then cash the rest of your tricks in the suit.

Ducking cannot lose but, as we have seen, playing the king can. Not playing third hand high drives out a winner by ducking.

On the last hand, your third hand play impacted how many tricks declarer scored in the suit led. It may not always do so. However, proper use of entries is often crucial in defense:

Dealer North

	42
	AQJ
	J10932
	AK6
95		KQJ63
107643		82
Q7		A64
Q832		1095
	A1087
	K95
	K85
	J74

Pass	Pass	1	1
2NT	Pass	3NT

Partner leads the 9 of spades. Having played third hand high since their bridge cradles, most defenders would play a spade honour without thinking. However, a little counting tells you that this will not defeat the contract.

How do you think the spades lie? If you play 'top of nothing' leads, you must guess whether West has 9-x-x or 9-x. However, if you lead either M-U-D (Middle-Up-Down) from three small cards, or low from any three cards in partner's suit, then you can presume partner has a doubleton and declarer A-10-x-x. (You will lead second highest from poor suits and fourth from suits with an honor.)

You can see 25 HCP (high-card points) between your hand and dummy. Declarer's 2NT bid shows 11-12, so partner will produce at most one trick. To defeat 3NT you must therefore take three spade tricks to go with your Ace of diamonds and partner's presumed trick.

Since declarer has two spade stops, they must both be neutralised before your only entry is removed. If you were to play the jack of spades at trick one, then declarer would duck and so put an end to your spade suit.

Ducking the first trick leaves partner with a spade to play when he gets in with the Ace of diamonds, your spades will be winners. Not playing third hand high maintains a link with partner.

The next exhibit features a classic defence. Although declarer can do the right thing he seldom will in practice:

Dealer South

	87
	Q6
	AJ10642
	K92
J9643		AQ5
KJ2		9754
83		K75
J83		765
	K102
	A1083
	Q9
	AQ104

1NT

Pass

3NT

Partner leads the 4 of spades. Let's say you play third hand high -- your ace. You can continue with the Queen of spades, which holds, and a third spade to the king. However, declarer plays on diamonds and whatever you do he will make ten tricks.

There is nothing you can do, you might think, but ask yourself this. What will happen if you play the queen of spades instead of the ace at trick one? Do you think declarer will dare to duck his king?

Think about it from declarer's angle. He would look a fool if West had AJxxx of spades as he would then go down even with the King of diamonds onside.

Surely declarer will take his King of spades and stake his contract on the diamond finesse. When you win the Ace of diamonds, you can cash the spade Ace and play a third spade so that partner can take the defense's fourth and fifth tricks.

If partner had led from the spade king, you would have lost nothing as the queen would win. When the queen loses, as here, it is safe to have fooled partner since you have the diamond entry. Not playing third hand high creates an entry for partner.

(Declarer's point-count was not relevant on this hand, but the bidding system used includes a variable 1NT opening i.e. 12-14 non-vulnerable and 15-17 when vulnerable.)

Breaking the 'third hand high' rule on the last two examples enabled you to keep a link between the defensive hands. Disrupting declarer's entries can be just as important:

Dealer South

	Q107
	J
	KQJ952
	984
8652		AJ4
Q1073		954
103		A74
K63		J1072
	K93
	AK862
	86
	AQ5

1	Pass	2	Pass
2NT	Pass	3NT

Partner leads the 6 of spades and declarer plays the seven from dummy. Before you detach any card you rightly pause to assess the complete picture.

Do dummy's diamonds worry you? The good news is that you have the Ace of diamonds doubly guarded, so you can limit declarer's tricks in that suit by holding off. However, once declarer has set up the diamonds, could he perhaps cross back to dummy to enjoy them?

Dummy has no club entry and you hope the Jack of hearts does not provide one. The primary danger is dummy's Q10 of spades. Assuming partner's lead is second highest from a poor suit, you cannot stop declarer making two spade tricks. What you can do is to prevent him gaining a spade entry to dummy. If you play the ace or jack at trick one, you surrender that power.

A look at the full hand shows that playing third hand high at trick one permits declarer to make ten tricks. Following with the 4 of spades leaves him without recourse. Not playing third hand high prevents declarer gaining a later entry in the suit.

Golden Rule One:

Playing Third Hand High can:

• Prevent declarer scoring a cheap trick;
• Knock out declarer's stop(s) and build defensive tricks;
• Avoid finessing against partner.

Not Playing Third Hand High can:

• Gain when you hold a tenace over RHO
• Drive out a winner by ducking
• Maintain a link with partner
• Create an entry for partner
• Prevent declarer gaining a later entry in the suit.