Source: http://cdn.acbl.org/nabc/2018/02/bulletins/db3.pdf

Dealer North. Both Vul

6 4
K 8 6 3
A 7 6 5
K 5 2
K Q 10 7
J 10 2
9 4 3
Q 10 7
J 9 3
Q 9
Q J 10 2
9 8 6 3
A 8 5 2
A 7 5 4
K 8
A J 4
West North East South
Pass Pass 1NT
Pass 2 Pass 2
Pass 4 End

Opening lead: K

Bidding commentary: With two four-card majors, bid hearts first when partner bids 2(Stayman). However, some bid the stronger major first in case responder also has both majors. If so, the partnership plays in the stronger 4-4 fit.

Eddie Kantar
Eddie Kantar

Defensive commentary: As East, when partner leads a king from the K-Q, denying the ace, signal encouragement with the ace or jack, not with a doubleton.

As West, if your king wins the trick, watch partner’s signal carefully. If partner has discouraged, denying the ace
or jack, declarer probably has the A-Jx-(x) and could be sitting in the bushes hoping you continue the suit. In this case, East encourages with the 9, so it is safe to continue the suit.

Play commentary: A spade trick must be lost in any event, so as South, duck the first round and win the second, retaining control of the suit.

Also, when you have a side suit divided 3-3 (clubs) that entails a finesse for a queen, save that suit until the end. Sometimes a friendly West will lead the suit, ending the need to take a finesse.

Play commentary 2: With side-suit shortness in spades and diamonds, both suits
under control after the first-round duck in spades, win West’s likely spade return, play the A and K and crossruff spades and diamonds. If you are overruffed, it will be with the high trump, so no matter. The way the cards lie, if you start by ruffing a spade before a diamond, you will score 11 tricks without needing the club finesse!