Deal 18
 
  4
OL: 2
♠ Q J 6
10 5 4
A K 3
♣ A Q 7 4
 
 WEST  NORTH  EAST  SOUTH
2
pass4passpass
pass

You are West. The bidding has been as shown.

You decide a trump lead is called for and lead the 2.
Your partner wins with the A and plays the J.
South lets this go to dummy's K, (but you know he has Q), then plays a trump back to his K, pulling the 2 outstanding trumps from West and East.

South's next play is the ♠3 from his hand.
Do you play your ♠A or not?

When you have made your choice click NEXT .
♠ A 9 5 2
7 2
8 6 4
♣ 10 8 5 3

A 3
J
  ♠ 3
K 6
6
 

 
Deal 18
 
  4
OL: 2
♠ Q J 6
10 5 4
A K 3
♣ A Q 7 4
  Play the ♠A.

Even if South doesn't have the ♠K he can establish a ♠ winner just by leading twice toward the ♠ Q J. That winner will take care of whatever black-suit loser he may have.

If East has a ♣ trick it is important to get it established soon.
So go up with the ♠A and play a ♣ through dummy's ♣ A Q.
When South tries the ♠ suit again EAST can win and cash his ♣K for the setting trick.

If you play low on South's ♠ play East will be forced to win the trick and he cannot profitably attack the ♣ suit from his side.

 Deal 19 
♠ A 9 5 2
7 2
8 6 4
♣ 10 8 5 3
♠ K 10 7 4
A 3
J 10 9 2
♣ K J 9
  ♠ 8 3
K Q J 9 8 6
Q 7 5
♣ 6 2