Slam Investigation

Slam Investigation

/ Sunil Khanna / Leave a comment

7. Slam Investigation  

Slam investigation should start immediately after concluding that partnership has superior set of cards, collectively. Slam investigation need not wait till a game stage is reached. In fact, earlier initiation provides a convenient sign off at game level if indications are that slam is unviable. 

In this chapter we will go as follows: 

  • Pre-Screening of Slam Investigation – 7.1 
  • 2nd level Cue Bids to screen slam suitability -7.2 
  • Quantitative 4NT invite -7.3 
  • Roman Keycards Blackwood Convention for trump slam – 7.4 
  • Gerber convention for No Trump slam – 7.5 

7.1 Pre-Screening of Slam Investigation 

During bidding certain triggers portend towards a good hand. To pre-screen such situations before the game level, we can consider the following actions:  

  1. When level 1 Major bid at opening, is receiving a jump response showing invitational bid.  

E.g. 1-3  

Here, a Pass by opener is Sign off or 4 is game. No further slam investigation is advised by the opener. However, a new suit bid by opener is initiation of slam investigation. It confirms game in opener’s 1st suit and is 100% forcing (being an Alert). The order of bids in various suits is sequential and in natural order of strain. We are now showing 1st or 2nd level of trick control in the that suit. i.e. presence of Ace, King, Void or Singleton. This called Control bid or Cue Bid (Discussed below-7.2). 

  1. Jacoby 2NT convention. This gadget immediately confirms game in partnership. Its design has inbuilt sequence of bids which can pre-screen possibility of slam. 
  1. After confirming 3NT game in Inverted Minor Raises, repeat of the opening minor at level 4 is Slam investigation. Partnership initiates Cue Bids and exit by sign off is at level 5 (in case pre-screening fails). 
  1. Bidding other Major by responder, post Stayman confirmation by opener, is slam investigation. New suit bids are now Cue Bids in sequential order. 

7.2 Control Bids or 2nd round Cue Bids 

With Level 2 Cue bids, we assess if our partnership controls 1st or 2nd trick in each suit. If any suit fails this test, then the slam investigation can be terminated by signing off at game. 

Cue Bids are 100% forcing. Exit is available only at game stage.  

Any new suit bid to initiate Cue Bids also confirms game.  

The order of cue bid suits is clockwise and sequential in natural order of strain.  

Cue bids show presence of Ace or King or Void or Singleton. 

Let’s take an example 

E.g.  W N E S 

P 1 P 3 

P 3 P 4 

P 4 P P 

P 

In this situation 3 is invitational bid by South. If North concludes that slam is possible, he need not bid 4 and instead initiate Cue Bids.  

3 bid above, confirms game and starts Slam Investigation. Shows presence of Ace or Kind of Spades with North or alternatively, a void or singleton to catch 1st or 2nd trick in .  

South bids 4 confirming that he has 1st or 2nd winning trick in Diamonds. Notice that he has skipped Clubs where he was obligated to inform his status of winning tricks (being next in line of cue bids). His skipping shows absence of top 2 winning tricks in Clubs in south hand. 

North signs off with 4 at Game stage. He concluded after looking at his hand that even he doesn’t have either of the top 2 winning tricks in . so he decided to restrict the bidding to game level in . 

Important point to note in these Cue bids is denial of control in top 2 tricks. If both partners are devoid of top 2 tricks, sign off in a game is the only solution as the slam will definitely fail. 

Note : If south had winning tricks in , his next bid will be 4NT to initiate 3014 Roman Keycard Blackwood convention. 

7.3 Slam Exploration by Quantitative 4NT 

When both partners have NOT established a FIT. It is mostly bid to play 6NT.  

  1. On partner’s 1NT responder goes directly to 4NT 
  1. On Jacoby Transfer or Stayman completion. Next bid of Responder is 4NT 
  1. 1-pass-2-pass-4NT like in 2 over 1 game forcing but before confirming the suit fit. 
  1. SMOLEN after failed Stayman by responder in opener’s first bid of No Trump. Opener’s 4NT next bid after SMOLEN will be quantitative because no fit is so far has been agreed. 
  1. Reverse rebid by responder is game forcing but 4NT immediately next will be quantitative because fit has not been confirmed. 

7.4 3014 Roman Keycard Blackwood Convention 

3014 RKBC comes into picture when we want to bid for a slam after both partners have agreed on a TRUMP suit for a game. There are many conventions like Splinters, Texas Transfer etc.. where pre screening of Slam is not possible using Cue Bids. RKBC in these cases is the first step towards Slam Investigation. 

One should avoid a slam unless they have all 5 Keycards or 4 Keycards+Queen of trump. Void too, becomes useful replacement of an ACE but it’s not a Keycard.   

  • Keycards are 4 ACES + King of TRUMP.  
  • Trump Queen is not a keycard but useful add-on 
  • Void can be a replacement of ACE but not a keycard 

Proceed as follows : 

Partner taking a call on SLAM Bids 4NT  

Responding partner bids and conveys as follows 

  • 5 saying I have 0 or 3 Keycards 
  • 5 saying I have 1 or 4 Keycards 
  • 5 saying I Have 2 Keycards but NOT Queen of Trump 
  • 5 saying I Have 2 Keycards and ALSO Queen of Trump 
  • 5NT shows 2 ACES and a void.  
  • 6 of side suit. 1 ACE and a void in bid suit. Suit strain is lower than agreed TRUMP suit. 
  • 6 of TRUMP suit. 1 ACE and void in a higher strain suit. 

Keep in mind sign off or going for a SLAM is prerogative of the 4NT bidding partner.  

Going further at level 6 we quiz the kings but in case of a trump game it’s generally not required. 

one should rarely bid 7 Trump called grand slam as it is a brave act.  

Note : Most popular method to investigate slam is 3014 Roman Keycard Blackwood Convention. However RKBC is not a complete picture on slam confirmation. We may have 3 Aces in partnership, but it can also happen that the missing Ace is accompanied by the King of same suit with opposition. Cue Bids cover this risk as they show 1st or 2nd level of suit control. 

7.3 Gerber – No Trump Slam Try 

The Gerber convention is a 4 response to a no-trumps bid. Like RKBC, it is a slam investigation bid that asks partner how many Aces and Kings you hold ?  

The difference in no trump slam evaluation vis a vis a trump slam lies in the different nature of keycards. In trump suit all aces+trump king are 5 keycards whereas in no trump we must have all aces and all kings. 

Gerber is only used for no-trumps for a systematic slam evaluation whereas, 1NT/2NT-4NT is natural and quantitative, inviting partner to bid 6NT as act of confidence in held hand. 

When does Gerber apply? Here are some standard rules: 

  • An immediate 4C response to any no-trumps bid (or overcall) is Gerber. 
  • A jump rebid of 4C in response to a natural no-trump bid is Gerber. 

4 Gerber Alert Response 

4 0 or 4 Aces 

4 1 Ace 

4 2 Aces 

4NT 3 Aces 

5 Gerber Alert Response 

5 0 or 4 Kings 

5 1 Kings 

5 2 Kings 

5NT 3 Kings