BBO Discussion Forums: Opener rebids 3NT in inverted minors - BBO Discussion Forums

Hi all, seeking crowd wisdom here.

In inverted minors, bridgebum, and wikipaedia both say that in a bidding sequence like this:

1D-2D
3NT

Opener is showing balanced 18-19HCP

While in something like this

1D-2D
2NT

Opener is showing 12-14 balanced

I can understand opener showing a minimum balanced hand with 2NT. But why is it that 3NT shows 18-19HCP and not 15-17HCP? How would you show 15-17HCP balanced with stoppers then?

appreciate some comments. Thanks in advance!

What strength is your 1NT opening?

A balanced 15-17 would open 1NT.

But as for the rest, I much prefer an inverted raise being forcing to 3 of the minor. That way 2NT can show both the lower and upper ranges to save space for slam investigation.

See https://bridgewinner...1m-2m-now-what/

mw64ahw, on 2021-November-24, 00:05, said:

15-17

I suppose that if you have 15-17HCP and don't open 1NT, that would mean you have a unbalanced hand.

Then 3NT can be used to show stronger hands? is that the reason?

ahtan, on 2021-November-24, 00:33, said:

Somewhat the opposite - the problem with jumping to 3NT is that you've skipped over two entire levels of bidding room, so it's almost impossible for responder to safely bid on if they're interested in slam.

The system described in the link above suggests 3NT show 18 points with 3 cards in the minor - the worst possible strong hand, so responder will almost always pass unless having plenty of extras themselves.

smerriman, on 2021-November-24, 00:46, said:

You're likely to have 4/5 cards in the minor as with 3 you would bid a Major first or have opened ♣s.i.e. 3343, (23)44 or 5(332). Or does the inverted raise deny a Major? I happen to play the other way round, but in an unbalanced !D context.

ahtan, on 2021-November-24, 00:33, said:

You have your answer.
3NT shows 18-19 3343, (23)44 or 5!D(332) with hopefully a stopper in any doubleton unless 2!D denies a Major

mw64ahw, on 2021-November-24, 01:51, said:

Exactly - over 1♦ it would only be 4432 (unless you opened that 1♣, in which case it's nonexistent), and slightly more likely over 1♣. But it needs to be rare and very precise given the space it wastes.

(And yes, to me the raise denies a major.)

Given the forum I think it is okay to expand a little bit.

There are multiple possible ways to play followups over 1m-2m(inverted). In fact, there are people who play different systems over 1♣-2♣* compared to 1♦-2♦*, which makes sense in an unbalanced diamond context.

The most natural agreement is that 2NT shows 12-14, 3NT shows any 18-19, any other 2-level bid (or 3♣ over 1♦-2♦*) shows a real suit and an unbalanced hand and 3m shows an unbalanced minimum without a side suit. You never hold 15-17 balanced because those hands open 1NT. If you play a weak NT (say, 12-14), then the 2NT rebid shows 15-17, and will be GF (in fact, this is the original system in which inverted minors became popular, if I'm not mistaken).
Jumps beyond 3m show a splinter, and confirm the minor suit will be trumps.

As smerriman already pointed out this is not an optimal set of agreements. Having to jump to 3NT with 18-19 hands wastes a lot of bidding space on the hands where you might need it the most - 18-19 NT opposite 10+ for the inverted minor. Even if you agree that this 3NT jump is forcing to 4NT you have deprived yourself of valuable bidding space for slam investigation. Furthermore, bidding 2NT on 12-14 balanced will frequently wrong-side 3NT (especially if the inverted raise did not deny 4M). It also leaves responder in no man's land - I'd push to game on most 11-counts with 5-card support in the minor opposite 12-14, and certainly would on all 12-counts, so the fact that 2NT is NF in these systems rarely wins points.

There are all kinds of changes you can make to this to address some of these, in particular by making 2NT forcing. A quick overview of three systems I'm familiar with:

• 2m forcing to 3m. 2NT is forcing, balanced, split range. The rest as above. You may need to bid 3m without support.
  
• 2NT shows 18-19, the 12-14 NT hand shows a stopper instead. 2M no longer shows four in an unbalanced hand but can be 'values'. The auctions 1m-2m; 2X-2NT and 1m-2m; 2X-2Y; 2NT are the only ways to bid 2NT NF.
  
• For balanced club, unbalanced diamond players: over 1♣-2♣*, 2♦ shows a generic minimum (often balanced but not always), and is the only way to get to 2NT (over this all 2NT by both players are NF). All other bids show an unbalanced not-complete-minimum, except for 3m which is NF.

I think the appropriate continuations depend considerably on your system. Inverted minors slot in very naturally with a weak NT system, but in a strong NT system you need to make adjustments. It's really not as simple as saying "we take the weak NT inverted minors, but every bid that used to show 15-17NT now shows 12-14NT", which would be the topmost system mentioned. The agreements on which hands to open 1♦ versus 1♣ with also have significant impact on good followups, so for example the bridgewinners article linked above would be quite awful in my preferred system.

DavidKok, on 2021-November-24, 02:55, said:

We play very differently in clubs using 2♦ as our better than minimum bid. (weak NT) It also matters massively if your inverts are GF or just F1 (as they are for us, and we allow 4M)

if 2N is GF as it is in a weak NT context, you can allow it to be 15-19 easily with an artificial 3♣ over it to disentangle the hand types so you can use 3N for any artificial meaning you want or any hand the asking 3♣ doesn't allow you to show.

Methods over 1m-2m (and I also include the specific sequence 1♦-2♣ in this family of bids) are very poorly defined.

Things to consider what to do with (assuming a strong NT):
does 2m deny a 4-card major.
rebids with:
balanced 12-14
balanced 18-19
hands with 4+ card support and shortness
4-4-4-1 hands after 1♦-2♣
hands with 6+ minor
true 2-suiters

Also, the question arises do you show stoppers? Many people nowadays don't show stoppers as it just telegraphs to defense the best lead and later defense.

If you look at Standard Modern Precision by D. Neil you will find the responses to be artificial showing different hand types. For example all balanced hands rebid 2♥ and all fitting hands with shortness bid 2♠. Using these methods opener is able to describe all possible hands and in some cases strength. Obviously, there are only strengths limited to 11-15 hcp so it is easier to know level than in standard. But is shows there are other ways to proceed rather than showing stoppers.

If you aren't finding inverted minors particularly easy, you could try playing 1m -2NT as game-forcing with support (in effect Jacoby in the minors)

Douglas43, on 2021-November-24, 12:19, said:

I'm sure this has benefits, but there are significant costs. Is 1♦-2♣ no longer GF to cater to 10-11 balanced, say 3=3=3=4 or the likes of (332)5? And if it does go 1m-2NT; what are the followups? How do you investigate 3NT versus 5m (versus slam?).

Playing weak (12-14) NT, I think you should play

1m-2m

2N - 17-19 (semi)balanced
3N - 15-16 (semi)balanced
suit bid - natural with an unbalanced hand.
jump in a new suit - splinter
4m - forcing, suggests slam

Great responses Thanks!

Since we seem to have expanded a little from my original question. I thought I'd ask a "How would you bid" question relating to inverted minors

Dealer is South and I'm sitting North.
1D-2D (inverted minor)
2H

I interpreted 2H as saying "No spade stoppers". I'm holding

S 975
H KQ4
D AKT72
C A9

I'm holding 16HCP. What do I do?

What do I do if my partner means something else by the 2H. She means "unbalanced 15-17HCP and just showing 2H as temporizing (forcing)". I have not seen this treatment in a casual search.

If 2♥ is natural, I would rebid 3♣. If 2♦ 100% denies 4M a bid of 3♥ is ideal instead. Assuming 3♣: if partner signs off with 3♦ you can bid 3♥ to show partial support, and partner will know that you are looking for spades to bid 3NT, or have set up a force for 5♦ otherwise and can investigate slam (although partner might play you for 2=3=4=4 or 1=3=5=4). In the case partner does not sign off with 3♦ you should make a slam try.

If 2♥ is artificial and shows nothing about hearts you need to have agreements about the followups. It is not possible to say what you should bid without knowing how your partner will interpret this bid. Thankfully your strength description implies that 2♥* is GF, so your hand could bid 3♦ (no spade feature, no NT-oriented hand, no club suit). But only if those are the meanings of 2♠, 2NT and 3♣ respectively.

On a more general note, it is seldom wise to play a convention without discussing the followups, or without considering what other bids were available. If 2♥* is "temporizing, unbalanced, 15-17" what do 2♠ and 3♣ show? Stronger hands? Weaker hands? Balanced hands? And what do jumps to 3♥ and up show? It sounds like your partner sprung this on you during the auction, in which case there is nothing you can do. Fix your agreements before it comes up again.

Yes, we need to fix our agreement.

my partner (post tournament) thinks 2H or 2S show stoppers in that suit and 15-17HCP unbalanced, forcing one round. 3 level new suit show splinters.

We actually made 12 tricks. She actually had
S AQJ4
H A862
D Q863
C Q

I had

S 975
H KQ4
D AKT72
C A9

At the time, I thought she was simply showing me heart stoppers with 2H, no stopper in spades. It seemed to me she was unbalanced (but no points signalled) with likely shortage in spades (hence no NT contract).

I counted 17 pts in mine (1 for short suit). Then jumped to 5D - this to me signals to partner we have about a total of 29 playing points (quantitative jump) if I assume she only has a minimum 13. She is free to jump to 6D if she has extras. Is this unreasonable?

Either way, assuming:
Option 1. 2H shows unbalanced 15-17 forcing 1 round or
option 2. 2H only shows stopped H suit.

How do I find a reasonable way to explore slam? In 2/1, I can use slow arrival to signal extras.

(yes, i know. Under her definition, she could have bid 3C to show splinters. She probably wasn't sure how I'd interpret it. But 3C to show splinters would work quite well too).

mw64ahw, on 2021-November-24, 00:05, said:

ahtan, on 2021-November-24, 00:27, said:

ahtan, on 2021-November-25, 00:01, said:

nullve, on 2021-November-25, 03:25, said:

..

ahtan, on 2021-November-24, 17:36, said: