Paul Soloway was one of the all time Greats in Bridge. His death in 2007 has left the bridge world poorer. Today's Defence, by him was a real gem. See if you can come any where nearer. Let me give you the West hand and the dummy along with the bidding first.
West led a Low Heart to Q and K, then Split his Heart honours on next round of the suit and was allowed to hold the trick. When West played next a Club through Dummy's K Q of Clubs, East discouraged by a Low Club. Declarer now played a spade towards Hand with QS being taken by Soloway's AS.
The position that emerged now was as under, with tricks 2 taken by the defenders & 2 by declarer. The crucial pomt of defence had been reached.
To down 2NT, the defense needs 4 more tricks. In defense, assumption of key cards on the base of the bidding and the play so far is very essential if the defense wants to outwit the declarer.
What do you do in West's Chair? And why? Do you go for the Diamond Suit now and if so, how do you proceed?
Before doing so let us gather the inferences from the bidding and the unfolding of the play so far. South opened ID and then rebid, INT, finally declining partner's invitational 2NT to clearly indicate a hand not above. South has already shown 3 hearts to the King. He opened ID showing more diamonds than any other suit, which leaves him with 6 black cards. He could not be holding a doubleton AC as the split club honours in dummy leaving him with 3 to the ace. Thus he is left with 3 spades with KQX which would make up his 12-13 points with 5 in spades 3 in hearts, 5 in clubs, surely holding AC as East had discouraged in Clubs.
When defence can work out the declarer's distribution and key cards as accurately like the palm of the hand, it is obvious that with the partner holding AD, diamonds need to be attacked immediately. That was easy, wasn't it? But how do you take 4 diamond, tricks to break the contract? It is here that the dividing line splits the ordinary player from the expert. Almost instinctively every West would play a low diamond but not Soloway who quietly laid down his KD first. Do you forsee why? Once Soloway gathered that AD lay with partner, he made sure of 4 diamond tricks even if partner did not hold 9D.
Look at those who lead a low diamond. East takes the AD, plays 6 D to West's KD who now is stuck. If he cashes JD - that's only 3 tricks with declarers 9D good. The declarers takes the heart finesse through West for his contract coming in the shape of 4 clubs, 1 spade, 3 hearts and a diamond.
Soloway's defence was a real gem netting in all 4 diamond tricks with J8 of diamonds poised over declarer's 97.
Well played, Paul Soloway who was nick named Babe Ruth of Bridge but was yet American Contract Bridge League's all time leading Master Point Holder and truly one of the Greatest Bridge Players the world has ever seen.

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North               West
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9 7 4                A 6
A 9 6 4        J 1 0 7 5
Q 1 0            K J 8 4
K Q 5 3          1 0 7 4
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THE BIDDING:

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West     North     East     South
---------------------------------
--       --        Pass       I D
Pass     1 H     Pass       1 N T
Pass     2 NT    ALL PASS       -
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North             West
9 7                  6
A 9                J 7
Q 1 0          K J 8 4
K 5 3            1 0 7
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