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1♦ Opening and Responses

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One Diamond Opening & Responses

The 1♦ Opening is a catch-all opening for any hand in the 11-15 point range that is not catered for by one of the other Intermediate Openings (1♥, 1♠, 1NT, and 2♣ in this system). As such it specifically denies the following holdings:

  • 5-card Major (Open 1♥ or 1♠)
  • 6-card Club suit unless very weak (Open 2♣)
  • 5-card Club suit with a 4-card Major (Open 2♣)
  • Balanced or Semi-balanced with a 5-card Minor in the 13-15 Point Range (Open 1NT)

In practice this means that the 1♦ Opening will always show one of the following hand-types:

  • Balanced or semi-balanced hands in the 11-12 point range
  • 11-15 points and any 4441 shape
    • Note: Standard Precision uses a 2♦ Opening to show 11-15 points and 4414 shape (Singleton Diamond). This Precision system does not follow that method and the 2♦ Opening is used to show 16-23 points hands with any 4441 shape
  • 11-15 points with a weak 6-card club suit unsuitable for a 2♣ Opening
  • 11-15 point hands with any 5-card or longer Diamond suit not covered by another opening (ie: not semi-balanced, not with a 6-card Club suit and not with a 5-card Major

Initial Responses

In response to the 1♦ Opening, partner bids along the following lines:-

1♦-Pass Partner should not be afraid to pass with a weak hand whether or not it contains Diamond support. It is rare that opponents will be able to profit significantly if they pass the hand out# when having the balance of the points, whether or not they have Diamonds. Normally they will bid or double for takeout.
1♦-1♥ 4-card suit, a 1-round force. Now all continuations are natural. Any Opener's rebid other than 1♠ denies holding 4-card Spades, and any rebid other than 2♥ denies 4-card Heart support. A rebid of 2♣ will usually contain 4-card Diamonds as well (unless a weak 6-card Club suit).
1♦-1♠ 4-card suit, a 1-round force. This response specifically denies holding 4-card Hearts unless the Spades are longer and Responder is strong enough to bid twice. Now all continuations are natural. Any rebid other than 2♠ denies 4-card Spade support. A rebid of 2♣ will usually contain 4-card Diamonds as well (unless a weak 6-card Club suit). A Rebid of 1NT might conceal a 4-card Heart suit. A rebid of 2♥ is a reverse promising 5-card Diamonds in addition to being maximum.
1♦-1NT 8-10 balanced. This bid specifically denies possession of a 4-card or longer Major. All continuations are natural. A reverse into 2♥ or 2♠ promises 5-card or longer diamonds as well. In practice, Opener will often pass this response unless minimum and unbalanced with both minors, in which case the best action will often be to bid 2♣ even if Opener's Diamonds are longer, since the 2♣ bid normally shows 4-5 in the Minors and Responder must have at least one 4-card Minor suit.
1♦-2♣ Natural and forcing to 2NT at least with 11+ points. Unless responder is strong enough to force to game by reversing this bid tends to deny possession of a 4-card Major. All continuations are natural.
1♦-2♦ Natural and forcing to 2NT at least with 11+ points. Unless responder is strong enough to force to game by reversing this bid tends to deny possession of a 4-card Major. All continuations are natural, but Responder should bear in mind that Opener may be 4414 shape with a singleton Diamond.
1♦-2♥ Alpha in Hearts with 16+ points. Game-forcing and firmly establishing Asking Bids.
1♦-2♠ Alpha in Spades with 16+ points. Game-forcing and firmly establishing Asking Bids.
1♦-2NT 16+ points balanced. Game-forcing enquiry. Opener rebids as follows:-
-3♣ 5-card Clubs and 4-card Diamonds, upper-range
-3♦ 5-card Diamonds, upper-range. May have a 4-card Major if 2245 shape
-3♥ 4-card Hearts, lower-range
-3♠ 4-card Spades, lower-range. Denies holding 4-card Hearts.
-3NT Any lower-range hand not containing a 4-card Major
-4♣ Weak 6-card Clubs, Upper Range
-4♦ 6-card Diamonds, Upper Range. Denies a 4-card Major as well.
-4♥/♠ 4-card Major with 5+ Diamonds, upper range and not 2452 or 4252 shape
1♦-3♣ Alpha in Clubs with 16+ points. Game-forcing and firmly establishing Asking Bids.
1♦-3♦ Alpha in Diamonds with 16+ points. Game-forcing and firmly establishing Asking Bids.

General Tactics

It will be seen from the above that Opener may have only a singleton diamond (may be 4414 shape or have short diamonds with a weak 6-card club suit). Despite this, Responder should not be afraid to pass with a weak hand and short diamonds. It will be rare that opps can and will be prepared to pass out the Opening when they have the balance of the points and stronger diamonds. If the Opening is doubled, at least one of the partnership will have a chance to rescue.

In the natural sequences above (particularly those starting with 1♦ -1♥/♠), the emphasis is usually on reaching a workable fit at as low a level as possible. It will often be profitable to accept a low-level Moysian (4-3) fit in a Major if the hand with the 3-card suit has a ruffing value.

Please note that a sequence such as 1♦-1x-2♣ does not promise a Minor 2-suiter. It does guarantee 5+ Clubs and will normally have 4-card Diamonds as well, but might be a weak 6-card Club suit, so Responder should be wary of supporting Diamonds above the level of 3NT until a 4-5 or 4-6 Minor 2-suiter is confirmed.

Lebensohl

Opportunities for Lebensohl in 3-suited sequences and after a reverse do occur over a 1♦ Opening. What you have to remember is that 1♦ does not show a Diamond suit of itself, but in a sequence such as 1♦-1♠-2♥ a 5-card or longer Diamond suit has explicitly been shown by the reverse into Hearts, so this is a 3-suited unopposed sequence, not to mention the reverse, so Lebensohl applies. Thus over 1♦-1♠-2♥

  • 3♣ is 4th-suit Forcing (a general rather than a specific 4SF here, as a slow 4SF in Clubs not possible)
  • 3♦ is constructive and forcing.
  • 2NT-3♣-3♦ is "to play"
  • 4♣ shows a Heart shortage, 3/4-card Diamond support, 5-card Spades and about 14-15 points
  • 3♠ is strong and forcing in Spades
  • 3♥ is forcing, agreeing Hearts.
  • 2NT-3♣-3♥ is invitational in Hearts
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