AB Multi 2D Opening bid is a multi-purpose opening bid for 3 types of hands. They are:
- A weak 2-suiter in Majors: ♥+♠, 55+, 5-11 HCP (the most frequent): Opener will rebid 3♥
- Strong Balance 20-22 HCP. May contains 5-cards Major: opener will rebid 2NT (or 3NT if opponent bids).
- A strong 3-suiter (4441) or (5440) with 17-22 HCP: opener will rebid 2♠, 3♣ -or- 3♠ to show 4+card holding on that suit. (i.e: natural bid)
- This “AB” Multi 2♦ is alertable [!]
- Strong Balance with 26+HCP and Strong 3-suiter 23+HCP are using “Kokish relay” via 2♣ opening. These hands are quite rare and special “protocol” needed to handle opening with no upper limit. See sequence 2♣-2♦//2♥-2♠//2NT.
(For Precision, recommended to use: 1♣-1♦//1♥-1♠//2NT sequence)
2♦ – ? – 2♥ : [!] 4+card ♠ – “transfer to ♠“ – 2♠ : [!] Do not have Spade. (Nothing to do with Heart)
That’s it. There is only 2 responds and it is just about Spade. No point information either.
How to remember
It’s all about Spade. And since opener can be strong, responder bid with “transfer-bid” style. (Bid 2♥ to show ♠ a.k.a “transfer to Spade) – Also, since opener need to be able to rebid 2NT, only 2♥ and 2♠ are available for respond bid
2♦ – 2♥ (have 4+♠) 2♠ : 3-suiter with 4+♠. Trump is set 2NT : Strong Balance 20-22 HCP. May contains 5-cards Major. 3♣ : 3-suiter with 4+♣. Since opener did not bid 2♠, then opener have short in S: 1♠-4-4-4 or 0♠-(544) 3♦ : 3-suiter with 5♦– Obviously opener can and should bid 3♣ (up the line) if (1444), so the opener hand’s must be 0-4-5-4. 3♥ : Weak 2-suiter in Majors, 55+ ♥+♠ 2♦ – 2♠ (No Spade) 2NT : Strong Balance 20-22 HCP. May contains 5-cards Major. 3♣ : 3-suiter with 4+♣ 3♦ : 3-suiter with 4+♦. Opener doesn’t have ♣. (444)-1♣ or (544)-0♣ 3♥ : Weak 2-suiter in Majors, 55+ ♥+♠
How to remember
Remember first, that 3♥ shows the weak 2-suiter in Majors. The rest is relatively “natural”: bid NT to show balance, bid 4+cards from the lowest rank to show 3-suiter. Amazingly simple.
~Visualization Aid: Typical Weak 2-suiter hand:
|8-HCP, ~7 losers|
Visualization Aid: Typical Strong Balance 20-22HCP:
|21-HCP, ~5 losers|
Visualization Aid: Typical Strong 3-suiter hand:
|18-HCP, ~5 losers|
After 2♦-2♥//3♥ -or- 2♦-2♠//3♥:
- 4NT = Blackwood (Total 4 Key Card). In the 2-suiter opening, usually, the opener doesn’t know what the denomination of the final contract, so cannot include King of Trump as one of the key cards.
- Any other bids are sign-off
After 2♦-2♥//2NT -or- 2♦-2♠//2NT: use the 2NT Bid Sequence.
After 2♦-2♥//(2♠/3♣/3♦): responder knows the opener’s exact distribution. So, the responder is setting the final contract based on typical HCP of opener and responder’s hand. If opener has extra, the cue-bid sequence can commence
The rest of the bidding would be for 3-suiter hand via 2♠ responds (no Spade responds). Keep bidding the 4-cards suit up the line until there is a fit or until 3NT. If a trump is set, 4NT would be RKCB (Total 5 key-cards, including the King of Trump)
2♦ – 2♠ (do not have ♠) 3♣ – ? 3♦ : 4+card ♦. No ♠, no ♣. 3♥ : 4+card ♥. No ♠, no ♣, no ♦. 3♠ : [!] Cue-bid fit ♣ 3NT : To Play 4♣ : Fit in ♣. Trump is set. Next: cue-bid or 4NT RKCB. 2♦ – 2♠ (do not have ♠) 3♦ – ? 3♥ : 4+♥. No ♠, no ♦. 3♠ : [!] Cue-bid. Fit ♦ 3NT : To Play 4♣ : Cue-bid. Fit ♦ 4♦ : Fit in ♦. Trump is set. Next: cue-bid or 4NT RKCB.
* Upon opponent’s double: all system on (i.e ignore the Double)
* Upon opponent’s overcall: uses D0P1/R0P1 style bid:
DBL = have 4+card ♠ (equivalent to 2♥ bid)
PASS = [!] do not have Spade.
In a competitive situation, opener may bid DBL or bid 3NT (if opener has stopper) to show the strong type.
Otherwise, Pass usually implies the weak 2-suiter variety. However, it is also possible opener wait for the final contract before making a penalty double.
If the opponent is using this opening, use these below as your competitive means:
- Use DOUBLE as “general double” (not a take out double). This means you just telling the partner you have 10+ HCP. No information about distribution at all
- Use DOUBLE also as “directing lead” for a hand with good Diamond but not enough to overcall
- Only overcall when the suit is really good with a good point as well.Especially if your suit is a Major. The most common holding for the opener is majors, so just wait.