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Roman key-card Blackwood


So far I have been guiding you away from the use of control-asking bids such as Gerber or four-ace Blackwood.

Rather I have guided you towards support bids and control-showing cue-bids.


However there is one situation in which one specific key-card asking convention is invaluable.


The eagle-eyed amongst you will have observed that in the slam examples so far I have kindly equipped you with at least the ace and the king of trumps.

If you happen to hold the trump queen as well in an eight-card trump fit then this will be sufficient to take out the opposition trumps 68% of the time (all else being equal), and if you are lucky enough to have found a nine-card fit then it will be sufficient to clear the remaining trumps as often as 90% of the time.


If your trump holding is not as solid as this then you will need to investigate it, and here cue-bidding is of little assistance.

Neither is the Blackwood convention in its simplest form or Gerber.

Roman Key-card Blackwood (RKCB) however addresses this problem directly.

(For alternative options less wasteful of bidding space when the agreed suit is a minor see the pages on Kickback, Redwood, and minorwood.)


Many teachers of the game will be surprised that I am introducing this convention in more or less its fully-fledged form, with most of the added extras, as one of my earliest conventions.  I include here everything you need to locate both the king and queen of trumps in addition to the outside aces.  My reasoning for this is very simple - if you do not include these devices then you probably shouldn’t be using a control-asking convention in the first place.  Get back to support bids, splinter bids, cue-bids, etc..


In this version of Blackwood the 4NT bidder asks for key-cards rather than aces.

Four of the key-cards are of course the four aces.  The fifth key-card is the king of the agreed trump suit.  In effect it is treated as a fifth ‘ace’.


The responses then are:-


5    1 or 4 of the 5 ‘aces’ (but see below)

5♦       0 or 3 of the 5 ‘aces’

5    2(5) of the 5 ‘aces’, without the trump queen

5    2(5) of the 5 ‘aces’ and the trump queen

5NT  2 of the 5 ‘aces’ and a ‘useful’ void.


Not everyone plays the 5NT response in exactly the same way.  A ‘useful’ void will normally be in a suit which has not already been suggested or implied as a source of tricks.


Traditionally the two lowest responses were interchanged, which is perhaps rather more intuitive.

The ‘1430 responses’ given above have now become the more common version played by serious partnerships.  They allow just a little more flexibility in using ‘the Queen ask’ (below) when hearts are the agreed suit and facing a one-key card response, but there is not much in it.  If you are both familiar with and happy with the older version then by all means stick with it.


You may also wish to incorporate some higher-level responses.

A possibility is discussed below under ‘responding with a void’.


Pass or correct


You may be concerned about the ambiguity inherent in the two lowest responses.


It need not concern you provided that you are agreed on an important principle.

If the response to 4NT is either 5 or 5 and 0 or 1 key cards are insufficient for the slam then the 4NT bidder should always ‘sign off’ in five of the agreed major (even if it is all but certain that partner has the higher holding).  


And the reason is that partner must always bid on when holding the higher number.

Let’s face it - if he can’t make the slam with three or four key cards opposite then he wasn’t even making game facing nought or one.

Beginner and above

This page last revised 6th Aug 2019

Assume that hearts or spades have been agreed.

Partner has shown one or four key cards.

Now you are asking about the queen of trumps.

You

LHO

Pard

RHO

?

?

?

?

4NT

-

5

-

5




Assume that spades have been agreed.

Partner has shown zero or three key cards.

Now you are asking about the queen of trumps.

You

LHO

Pard

RHO

?

?

?

?

4NT

-

5

-

5




A K J 6 5

8 3

A K 7 5

K T

If 4NT gets a one ace response you can now bid 5for the queen.

Without it partner will bid 5 and the auction will end.

With it you will reach 6.

You

LHO

Pard

RHO

1

-

2NT

-

3

-

3

-

4

-

4

-?

A K T 9 5 4


A K 5 2

K

3 is a cue-bid denying the A.  (Many will play it as natural.)

Now you can introduce RKCB.

Partner will respond 5 or 5 (he can only hold one key-card) after which your bid of 5 asks about the trump queen.

You

LHO

Pard

RHO

2

-

2

-

2

-

3

-

4NT





Baling out


Playing standard four-ace Blackwood it is possible to stop in a contract of 5NT by bidding a new suit at the five-level.

This could present a problem if such a bid might be a queen-ask.


The easiest solution is to dispense with the baling out option.

Alternatively, a serious partnership should agree on either restricting the queen-ask to suits below the agreed suit, or on using the lowest available suit as a queen-ask whether below or above the agreed suit, and only retaining a baling out option only if a further new suit is available at the five-level.


Responding with a void


An extension to the standard set of responses allows responder to show a count of aces together with a void.

This is not a widely known part of the convention in normal club play but it has much to commend it.  However it should be noted that there may well have been a more straightforward way of showing the shortage at some earlier stage in the auction.

As these responses lead to at least the six-level it goes almost without saying that responder should not make any of these bids if he has any reason to suspect that the combined strength of the two hands might be insufficient.  In particular, the void should be ‘useful’ which in general means that it should not be in a suit which partner has bid naturally.


There are possible variations on the scheme of responses but they will all resemble the following to some extent.


In response to the 4NT Blackwood ace-ask:-


5NT promises two key-cards and an unspecified void;

six of a suit (not trumps) promises one key-card together with a void in the bid suit;

six of the trump suit promises one key-card together with a void in a higher-ranking suit.


Some pairs add a further bit of jiggery-pokery over 5NT involving a relay of 6 after which it will frequently be possible to locate the void, and by implication the location of the two aces.

K 3

A K J 6 5

A K 7 5

K T

Partner has two-key cards, not the Q, and a void.

Do you even care where the void is?

Bid 6.

You

LHO

Pard

RHO

1

-

3

-

4NT

-

5NT

-

?




K 3

A K J 6 5

K Q 7 5

K T

Partner has one key-card.

Time to call it a day.

Bid 5.

You

LHO

Pard

RHO

1

-

3

-

4NT

-

5

-

?




K 3

A K J 6 5

K Q 7 5

K T

Partner has one key-card and a void in clubs.

It’s not cast-iron but 6 must stand a chance.

Bid 6.

You

LHO

Pard

RHO

1

-

3

-

4NT

-

6

-

?




K 3

A K J 6 5

K Q 7 5

K T

Partner has one key-card and a void in diamonds.

Not really what you wanted to hear.

Twelve tricks are far from certain, but you have made your bed and now you must sleep in it. Bid 6.

You

LHO

Pard

RHO

1

-

3

-

4NT

-

6

-

?





Combining your methods


In the section on cue-bidding I stressed the importance of locating specific side-suit controls, and that this possibility is lost if you jump too quickly into a control-asking convention.  Now that I have introduced situations in which it is necessary to use RKCB to locate the trump honours the obvious question is ‘what do I do if I need both pieces of information?’


Fortunately there is a simple solution.  Provided that the partnership has set the suit at a low level with some kind of support bid then there is frequently space in which to bid out the side-suit controls below game-level before using RKCB to find out about the trump holding.


Asking for kings


As in ordinary Blackwood a bid of 5NT by the original Blackwood bidder would be asking for kings (the ‘other’ three kings).

The most common system of responses uses a simple scale of 0,1,2,3, but note that I prefer an alternative method - the specific king ask.


Note that the bid of 5NT already commits you to a small slam.  The only purpose in locating the kings would therefore be in search of a grand slam.


It follows that you will never make this bid unless holding all five key-cards, the queen of trumps, and what appears to be a solid combined trump holding.


With this understanding partner will, on occasion, be able to jump directly to the grand himself.


So, if you want to be in a small slam but have no interest in a grand slam - just bid it.


Note that all of these bids assume that you have already determined the existence of sufficient playing strength to stand the level towards which you are pushing.


The standard warnings


I trust that you are familiar with these:-


do not start using any form of Blackwood if you cannot stand any response.


Watch out for the 5NT response in this respect - it tends to catch you unawares - but 5 is also likely to take you too high if you hold just one key-card and you are missing the queen of trumps;

Blackwood is hardly ever the correct course of action when a minor suit has been agreed (for the reason above - there may well not be the space to stop at the five-level);

if specific side-suit controls are critical then try to find out about them before using RKCB;

do not ask for kings unless you hold all five key-cards (and the queen of trumps if appropriate) between you (and a bit more).


K T 9

T 7

A 8 5 2

A 9 5 3

You bid 5 to show 0 or 3 key-cards, and partner signed off in 5.

With 3 key cards you must bid on - you have no choice.

Bid 6 denying the Q.

You

LHO

Pard

RHO



2

-

2

-

2

-

4

-

4NT

-?


‘Correcting’ informatively


The spotlight now switches to the partner who first responded 5 or 5 to the 4NT key-card ask.


Clearly with 0 or 1 key cards he will just pass.


With three or four key-cards and missing the queen of trumps he will bid six of the agreed suit.


Holding the queen of trumps he should make some other bid below the level of the small slam:-


5NT would suggest the queen of trumps but with no further significant side-suit feature;

A bid in a new suit would suggest the queen of trumps together with a side-suit feature - typically a king.  Wouldn’t you just love to hear a 5 response on the hand above?

8 3

A K J 6 5

K Q 7 5

K T

2NT agrees hearts and is forcing to game.  5 promises 0 or 3 key-cards.

Partner almost certainly holds the three missing aces, but just bid 5.

He will raise to six whenever he holds three key-cards, and may be able to offer further valuable information on the way (see below).

You

LHO

Pard

RHO

1

-

2NT

-

4NT

-

5

-

?





Showing the Queen


Authorities are divided on the negative response.  Some play it as the next suit up, and some play it as a reversion to the trump suit.

My choice is that a return to the trump suit denies the queen, and that is the method you will find in what follows - it allows you to give a useful meaning to the bid of the next suit.  If you choose the alternative agreement it will make little difference.


Any other bid will promise the trump queen or some equivalent holding.

By an equivalent holding I mean that if you believe that you have a ten-card or better fit between you then you can bid as if you hold the queen, even when you don’t. With three cards out, the queen will drop under the ace-king 78% of the time.


The simplest way to show that you do indeed hold the much sought-after queen is to jump to the small slam in the agreed suit.


However, your partner could still have his eyes on higher things, so if you have an additional feature in a side-suit which you have not yet shown then now is the chance to show it - a sort of free cue-bid.

An alternative is to show the number of ‘other kings’ held along with the trump queen on a step scale.


If you yourself can see that a grand slam might now be a possibility but you have already shown all your features then a bid of 5NT (or 5 if hearts is the agreed trump suit) informs partner that you hold the queen, and invites him to show any further features on his way to the small slam.


The Queen Ask


The strength of the convention lies in its ability to locate both the king and queen of trumps.

If partner holds two key-cards then you already have this information.

For any other holding the Blackwood bidder can bid the next suit up other than the agreed trump suit to ask about the trump queen, provided that he has sufficient strength and the bidding space in which to take such an action.

Context  -  The continuing auction - in the slam zone - Blackwood etc..