Grand day for slams

Many pairs play that, in reply to a 1H or 1S opening, a game-forcing raise is shown by a response of 2NT “Jacoby”.

If playing Jacoby, the immediate response of 2NT to a major opening shows 13+ points and, ideally, at least 4-card support. Opener may then show a shortage (singleton or void) if the hand has one by bidding the short suit at the 3-level. Here is a good example of Jacoby in action

WEST          EAST
♠ 6           
 A542
A9872       
 K6543
A65         
 K2
A765        
♣ K3

WEST     EAST
1H       2NT Jacoby
3S       ?

West opens 1H and East responds 2NT, Jacoby, showing a good fit and game points. When West shows the singleton, East knows the small spades can be ruffed. The three cards East should be worried about are the missing aces. Use Blackwood and when partner shows all three, bid 7H as there are no losers (assuming hearts divide 2-1, the normal break).

Instead of showing a shortage at the 3-level, opener may jump to the 4-level to show a good 5-card suit:

Dealer South, nil vul.

          NORTH
          
 AKQ9
          
 KQ6
          
 A62
          
 987
WEST                EAST
 —                  8543
 9843               5
 J8754              KQ9
 KQJ3               T6542
          SOUTH
          
 JT762
          
 AJT72
          
 T3
          
 A

SOUTH    NORTH
1S       2NT
4H       4NT
5H       7S

Over North’s Jacoby 2NT, South prefers to show a good 5-card suit (by bidding it at the 4-level) rather than the singleton.

After South’s reply to Blackwood, North counted 12 top tricks: five in each major (assuming normal breaks) and the two minor suit aces. Once trumps are drawn, it should be possible to run the hearts and discard from one of North’s minors, then gain an extra trick by ruffing “in the short hand”. At least that was North’s thinking in bidding the grand slam.

After winning the club lead, declarer played a trump to dummy’s ace and discovered the 4-0 break. Drawing trumps then running the hearts to discard the diamond losers from North will no longer work, because if four rounds of trumps have been drawn, North will have no trump left to ruff a diamond with.

The solution is known as a dummy reversal, whereby declarer ruffs in the long hand (the hand with longer trumps). At trick three, lead a club for South to ruff. This first ruff doesn’t actually gain a trick, because that fifth round of trumps had been counted as a winner anyway. Lead a spade to get back to dummy, then lead the other club and ruff it.

 This time a trick has been made with a trump that would have fallen under dummy’s, had trumps been drawn, and that is the extra trick needed for the grand slam; it is time to draw trumps and claim.