[Ethel]

Would someone kindly tell me the name of the convention and where I can find out more information about it?

Opening bid is: 2♦ Responder bids 3♣ Neither bid is alerted,but 2♦ is an opening NT hand with 18 + points and 3♣is Stayman. Is this convention allowed under General Chart in the ACBL or is it Mid-Chart? Is the convention permitted at the club level? Thanks

[Elianna]

Ethel, on 2011-February-11, 12:43, said:

Would someone kindly tell me the name of the convention and where I can find out more information about it?

Opening bid is: 2♦ Responder bids 3♣ Neither bid is alerted,but 2♦ is an opening NT hand with 18 + points and 3♣is Stayman. Is this convention allowed under General Chart in the ACBL or is it Mid-Chart? Is the convention permitted at the club level? Thanks

Many people call a 2♦ opening bid showing 18-19 balanced a "Mexican Diamond". I have no idea where the name came from, or regular replies to it.

According to the ACBL convention charts, it is a general chart convention, as it is a strong bid (but it should be alerted). See opening bids #5a for the rule allowing it, and you can look at the alert chart to see that it is alertable.

As clubs are free to set their own convention chart, I can not say if it is permitted at the club level, but if they claim to be strictly following the GCC, then it should be allowed.

[mtvesuvius]

It sounds like a variation of a Carousel (a.k.a. Mexican) 2D.

There was an article about it in the first bridge bulletin I ever read, back before they switched to the "Magazine" format. I think it was sometime between July and December 2002, sorry I don't remember more.

I would imagine it is legal, since the ACBL GCC says:

Quote

5. TWO DIAMOND ARTIFICIAL OPENING BID indicating one of:
a ) a strong hand.
b ) a three-suiter with a minimum of 10 HCP

EDIT: I see Elianna has beat me to it

[blackshoe]

It's GCC legal.

George Rosenkranz has been playing around with the 2♦ opening in the context of his Romex system for more than half a century. I've seen several older versions (no longer used in Romex) called variously "Mexican 2♦" or "Romex 2♦". Rosenkranz himself calls the current opening as used in the Romex system "Mexican 2♦". That one shows a balanced 21-22 HCP or a GF with primary diamonds. The current responses are complex, so I won't get into them here. There was a simple set of responses in Bid to Win, Play for Pleasure, where 2♥ showed 0-5 HCP, 2♠ 6-10, and 2NT 11+. Over the 2M responses, opener would rebid 2NT with the balanced hand, and thereafter the systemic responses to a 2NT opening (Romex Stayman, Jacoby Transfers, a couple of other things) would apply.

Nicu Kantar, in Bridge: Classic and Modern Conventions, calls the current Romex opening "Romex 2♦" and calls opening on a balanced 18-21 "Mexican". Responses:

negative (0-6 points): pass w/♦, 2M/2NT natural, 3NT puppet to 3♣ (after which responder will pass)
positive (7+ points): 3♣ Stayman, 3♦ puppet to 3NT (responder can make a slam try over 3NT with 12+), 3M natural.

There is, iirc, a discussion in Rosenkranz and Truscott's Bidding on Target of using a Mexican 2♦ in a standard or 2/1 context to firm up the NT ladder, but I don't remember all the details.

[mtvesuvius]

I'll do a bit of digging around my room later, I know I have both Bidding on Target, and the article on Mexican 2♦ from the ACBL bulletin.

[mike777]

search for "mexican 2d" in quotes here in the forums and you will find many articles.

GCC legal.

In most versions


2d=2s(forces 2nt)
2nt(forced)=3c=stayman.

In practice about 80-90% of your auctions start out:
2d=2s forcing 2nt
2nt=etc...


2d=3c in many versions is transfer to diamonds or forces 3d. Responder will have long one suited d hand or two suited d and some other suit.