Sneak Attacks
Q 4
A Q J 3 2
J 9 5 3
10 5
10 3 2
K 10 4
K Q 7 6 2
J 2
9 7 5
9 8 7 6 5
A
A K Q 4
A K J 8 6
—
10 8 4
9 8 7 6 3
Notrump
With East/West on lead, they can unblock the diamond ace, cross to
the club jack, take two more diamonds, and three more clubs.
But North/South can only take six top tricks. How do they stop
East/West from taking seven tricks? They take the top five spades,
North pitching two hearts and a club, then South exits a club.
This sneak attack in the opponents' club suit forces East/West to
spend one club entry or another before the diamond ace is unblocked.
If West plays low, East winning, then East can unblock the diamond
and cross to the club jack for two more diamonds, but then they
can't cash the remaining two clubs. If West wins, he has used his
club entry before East has unblocked the diamond ace.
Either way, North/South get two more tricks, either a diamond and a
heart, or two hearts.
Spades
With East/West on defense, they unblock the diamond ace, cross to
the club jack, and take two more top diamonds. Now West must shift
to a spade, another attack in an a strong suit held by the opponents.
South's spades are strong enough that he can afford to ruff a club
in dummy with the queen for his seventh tricks, but this spade lead
lets the defense prevent it. North appears to have a diamond trick
established, but there in no entry to the North hand after drawing
trumps, and East just ruffs if North plays the diamond before trumps
are drawn.
If East/West get into an unlikely spade contract, North/South just
defend as they defend against notrump, running five spades and
exiting in clubs.
Hearts
If North/South declare hearts, the defense starts as usual - diamond
ace, club to the jack, two more top diamonds. Then West leads a
club to East, and East leads a third round of the suit, West ruffing
high, establishing a third trump trick for the defense.
If East/West declarer hearts, the defense starts with three top
spades, North pitching a club. When South leads a fourth spade,
North pitches his last club:
Pitching the clubs has severed the East/West hands almost completely.
If East/West try to avoid giving North two club ruffs with his
small trumps, they are stuck leading hearts and diamonds. On heart
leads, declarer gets three natural heart tricks (with the king
onside) and every time exits in diamond. If East ruffs the fourth
diamond (which will be good,) that sets up a long heart in the
North hand.
Diamonds
With East/West declaring in diamonds, the defense starts with a
spade to the queen,
♥ A, heart ruff, two more top spades,
North pitching a club, and a fourth spade at this position:
North pitches a club whatever East/West do. The defense has taken
five tricks, and North has a natural trump trick coming, so they
just need one more trick. If East ruffs the spade with the diamond
ace, that promotes a second trick for North. Bad plan. Similarly
if West ruffs high. So West must ruff low.
West can't lead a heart (it gives South another ruff) or a club
(North ruffs and gives South a ruff) so he must lead a diamond,
but then East is stuck leading clubs or hearts, and the defense
scores its seventh trick.
The position above is interesting. If West ruffs low and North
chooses to overruff, East ruffs with the ace, crosses to the club
jack (since North still has one), takes two top diamonds and exits
a diamond, retaining a club entry still left to East and no more
losers. Only the club pitch works here.
If North/South declare diamonds, the defense starts with a diamond
to the ace, a club back to the jack, two more top diamonds and and
then more clubs. Whenever North ruffs, West is left with two small
trumps, and the defense ultimately takes five diamonds and two
clubs.
Clubs
If North/South declare clubs, the defense attacks in its usual
fashion - diamond ace, club to jack, two top diamonds, and three
more clubs.
If East/West declare clubs, the defense starts with two top spades,
a spade ruff, the heart ace, South pitching a diamond, and finally
the club ten.
This has the usual affect of forcing East/West to win a club entry early,
but it seems like East/West should be able to make seven tricks some way.
How will North/South manufacture three tricks?
Say East wins in hand, cashes the diamond ace, and leads a heart.
South doesn't take the bait, and instead pitches his last diamond
and West is wins the king to this position:
If West plays a top diamond, South ruffs and exits a club. On a second
top diamond, South ruffs again and exits a spade, East force to ruff high.
Other lines are similar.
Complexity
This is another complexity three deal, with only the diamonds suit being
par-zero on its own.