30th September 2020

A deal from a Manchester online league match.
Dealer S Game All.

S 2
H AJ10986
D A3
C AJ109
   


   
S AKJ1053
H
D 8542
C K43

South
West
North
East
1S Pass 2H Pass
2S Pass
3C Pass
3S Pass
4S Pass
Pass Pass


You reach four spades on the above auction.
West leads the ten of diamonds, form a plan.

Solution


The key play is to duck the first diamond. 
This forces the defence to play a trump at trick two to prevent a diamond ruff, while you retain the ace of diamonds as an entry.
After the trump switch you draw four rounds of trumps, they break 5-1 with East having the singleton queen.
Then the king of clubs and a club to the ace, it doesn't help West to trump this.  If West throws a diamond on the ace of clubs you can ruff a heart in hand cross to the ace of diamonds and ruff another heart in hand for six trumps tricks, two clubs and the red aces.  If West throws a heart on the ace of clubs, then ace of hearts throwing a diamond, and the jack of clubs.  East wins the queen of clubs but the only other trick the defence gets is the winning trump as there is a winning club in dummy to throw another diamond on.

The full deal was

Dealer South
S
2
   
Game All
H
AJ10986
   
    D A3
   
    C AJ109
   
S
98764
    S
Q
H
Q542
    H
K73
D
1096
    D
KQJ7
C
2
    C
Q8765
    S
AKJ1053
   
    H

   
    D
8542
   
    C
K43
   


Thanks to Royce Alexander and John Holland for analysing this deal