2/1 Non-Forcing

Ideas by Rob Forster, version 2

The original Seismic 2/1 Non-Forcing methods over 1M seemed interesting but had difficulty with the many strong hand types included in the forcing NT response (which covered all non-fitting invitational or better hands, and constructive hands with doubleton support). For this reason and for simplicity most Seismic partnerships had chosen a 2/1 Game Forcing alternative. While this is certainly familiar and effective, I think with some improvements and modifications the advantages of 2/1 GF can be combined in part with those of 2/1 NF in the following system:

  • 1M-2C natural 3+ suit, forcing 1 round but does not promise a rebid (~11+ points)
  • 1M-2D natural NF, usually 6+ suit (~4-10 points)
  • 1S-2H natural NF, usually 6+ suit (~4-10 points)

The 2/1 NF bids of 2D and 2H are similar to weak 2 bids, usually 6 cards although possibly only 5 with shortness in opener’s major.

For complex reasons, it seems right to single out a 2/1 bid in clubs as forcing, consequently stronger in values (at least invitational) than the other 2/1 NF bids. The 2/1 bid of 2C includes the following hand types:

  • invitational hands with long (6+) C, could have a side suit.
  • all the normal 2/1 GF 2C hands, including balanced hands with 3-card M support
  • all GF two suiters with clubs (even if it’s the shorter suit, like 5H/4C)
  • balanced GF hands looking for 3NT declared by opener

The remaining GF hands start with 1NT forcing. Recall that the direct major suit raise structure for Seismic covers all hands with 4+ support. In addition, compressed strong jump shifts also cover many slam invitational single suiters. A direct 3NT raise includes balanced 33(43) raises with extra values (15-17). What GF hands are left?

  • GF one suiters in D or H, either without slam interest or a good enough suit to make a compressed jump shift.
  • GF two suiters in D + H, either longer.
  • GF balanced with 3-card M support but short clubs (hence not suitable for a 2C bid)
  • GF balanced looking to declare 3NT

After a 1NT forcing bid and opener's rebid, weaker than GF responders make their typical rebid as in 2/1 GF methods: invitational hands will raise one of opener’s suit(s), bid 2NT, or bid their own good/long suit at the 3 level (only for H and D). All the new suit (3rd suit) rebids at the 2 level and 3C show various GF hands. Specifically,

1NT Forcing Auction Game Forcing rebids by responder
1M-1NT-2C 2D, 2OM, 3C
1M-1NT-2D 2OM, 3C
1H-1NT-2H 2S, 3C
1S-1NT-2S 3C
1S-1NT-2H 3C
1M-1NT-reverse or jump shift anything besides pass or correcting to opener’s first suit

Aside from the invitational rebids by responder of 3D, 3H, and 3M, higher bids can also show suitable GF hands. 3NT is a natural choice, as are splinters (above 3M) in support of the last bid suit.

One advantage of this structure is that when responder is GF with D and/or OM, opener is likely to have club length. This means his response to 1M-1NT forcing is more often 2C, allowing responder to establish a clear GF auction at a low level and with several choices to accurately describe his hand.

Responder’s GF rebids after 1NT forcing:
Here are some first guesses for what different GF responding hands should chose, when they get a choice of GF replies to opener’s rebid. Not listed is the obvious 3NT choice in all cases. Note that club or M shortness (2-) is likely for responder on these auctions.

Auction Bid Meaning
1S-1NT-2C 2D natural 4+ (D or D > H)
  2H natural 5+ primary hearts
  3C 3S and 2- C, agrees S
1H-1NT-2C 2D natural 4+
  2S 4S/5+D (other S + D hands start 1S)
  3C 3H and 2- C, agrees H
1S-1NT-2D 2H catchall (H’s or D fit)
  3C 3S and 2- C, agrees S
1H-1NT-2D 2S 5+D (could have 4S)
  3C 3H and 2- C, agrees H
1H-1NT-2H 2S 5+D (could have 4S)
  3C 3H and 2- C, agrees H

Opener’s rebids when responder has a single GF call

1S-1NT-2S-3C 3D asks for clarification
    3H 6+ hearts
    3S agrees spades
    3NT 5+ diamonds (could have 4H)
  3H fragment 3H
  3S long spades 7+
  3NT C stopper
1S-1NT-2H-3C 3D asks for clarification
    3H 4+ agrees hearts
    3S 3+ agrees spades
    3NT 6+ diamonds
  3H 5/5+
  3S 6+/4
  3NT C stopper

Opener’s rebid after 1M-2C:

1S-2C-2D artificial, max values (auction now natural and GF)
1S-2C-2H natural 4+, min NF (invitational hands can pass or bid 3C)
1H-2C-2S natural 4+, min NF (invitational hands can pass or bid 3C)
1M-2C-2M natural 6+, min NF (invitational hands can pass or bid 3C)
1M-2C-2NT 4+D, 1- clubs, min NF (invitational hands can pass or bid 3C, 3D GF/NF?)
1M-2C-3C 2+ clubs, min NF (invitational hands pass)
1M-2C-3X distributional maximum 6/5+
1M-2C-3M distributional maximum 7+

Observe this scheme of natural minimum responses for opener’s rebid (in H, S, C) should allow responder to find the best strain with 2 suited invitational club hands (i.e. 4H/6C after 1S, 4S/6C after 1H) by passing or pulling to 3C.

2/1 NF Continuations (Opener’s Rebid):
besides the obvious and recommended pass option, we have: raises of responder’s suit...

1M-2X-3X blocking weak raise, 3+ support
1M-2X-2NT sound raise, 3+ support, inviting game (3X rebid declines)
1M-2X-3NT To play, probably
1M-2X-4X ? To play if 4H, blocking otherwise?

splinter raises of X with big fits and maximums starting with 3M+1, i.e. 1H-2D-3S or new suit bids at the 4 level by opener.

weak non-fitting actions...

1M-2X-2M natural, good 6+ suit, typically no tolerance for responder’s suit
1S-2D-2H natural, 5/5+, no tolerance for responder (pass/correct)

strong non-fitting actions...

1H-2X-2S natural, very distributional maximum
1M-2X-3Y natural, very distributional maximum
1M-2X-3M natural, very long suit, maximum
1M-2X-4M natural I suppose