Mijumaru Blue Club

Welcome to Mijumaru Blue Club! This bidding system is largely based on Blue Club. Changes are made with my improvisation.

We use the distribution syntax and abbreviations provided by WBF.


The ACBL convention card of this system is at


Notable differences from the original Blue Club

Strong opening auctions are one point lower.

The 1NT opening is 14–16 HCP to fit the ranges above. Modern 3-point ranged strong notrump works better than a weak or wide-ranged one.

The precedence for opening a 4-card suit is > > . Opening 1 for 44 in majors provides better constructiveness.

We don't care about suit quality in constructive bidding. Responder does not consider 3-card suits as biddable.

We use natural 2/1 over 1 and swapped 2/1 over 1 .

The responses to 1 are natural Polish-like instead of control-showing. MAFIA applies to minimum game force.


Hand evaluation

NLTC is a good single hand evaluator but not very additive. It suits preemptive initial actions but not for showing supports. I have a blog article on that topic.



We evaluate stopper quality as GIB does.


Opening bids

Note that we don't open 11 HCP balanced hands. Unlike aggressive sibling systems, we keep our opening range narrow for easier responses.

Choice of suit openings

Contrary to popular belief, a modern Blue Club is pretty natural.


Sometimes we open the secondary suit on purpose. We canapé for maximum non-club two suiters, planning to reverse in the primary suit later.

There is also canapé for minimum 4M5 . We open 1M so that 4M5 hands in the 2 opening are strong enough for the 2 relay.

The notrump ladder

Strong 1 opening

We use Polish style responses to the 1 opening. These responses are derived from canapé style in "PC - Meckwell Lite Precision Club" by Edward Piwowar:


These exactly 4-card 1M responses are canapé style, i.e. there can be a longer side suit. With (54) in majors, we usually bid the 4-card major first. However, with a 45(xx) mild slam try (11–13 HCP), we bid 2 and then rebid 3 .

Negative 1 response

There are three variants in the 1 relay:

We employ a bidding structure similar to Kaplan Interchange to try to locate a partscore at a low level.

Positive 2M responses

The 2M responses are game-forcing and show 5+ cards. Except 45(xx) mild slam try, the other major is not exactly 4 cards.

Over 1 -2 , things are pretty natural. Over 1 -2 , however, bidding 3 would be too high if we want to find both 5-3 and 6-2 fits. Therefore, we swap the meanings of 3 and 3 .

With heart support over 1 -2 -3 , there are several ways to reach 4 . In general, we want to cede declarership with a weak hand, so we assign weaker support to bids with higher transfer rate. However, we can also reuse the weakest forcing bid for strong hands (~2+ tricks above minimum) to save bidding space.

The 3M rebid sets the trump suit. If opener wants a choice of games, bid 2NT instead.

The 1 opening

Major suit openings

Unlike most strong club systems, we play 2/1 FG here. Since the 2NT response is conventional, the wide-range 1NT must include invitational hands. Most of the time, 1NT is a decent contract for a minimum opener. F2NT would miss the chance to stop at 1NT.

We swap 2 and 2 over 1 , inspired by Twisted 2/1 by Ting-Yu Ye (TpKotoba).


When there are 5 hearts in 1 -1NT, it must be an invitation without a spade fit.

Natural invitational 2/1 by passed hand

Strong notrump opening

We use the French-style 4-way transfers to preserve the natural invitation. We invite naturally rather than via Stayman because 2NT hides information of the declarer.

The responder tries to show a major first always (MAFIA). The only exception is not to bid Stayman with (4333), a hand so flat that playing notrump is a better idea.


Excluding opener's 5-card majors, the Stayman has its traditional meaning or a Garbage Stayman.

The Garbage Stayman takes advantage of that opener will eventually rebid within 2 , so we can bid 2 as a weak takeout of clubs and pass in the next round.

We only employ Smolen transfers at the 3-level. The 2-level invitations are natrual so that we have a chance to stop at 2 .

The step of 1NT-2 -2 -2 allows us to always choose the better major fit. This is why the opener rebids 2 with 44 majors.

Jacoby transfer

The opener always accepts Jacoby transfers. We super-accept with maximum and 4 trumps. We hide the doubleton just below the trump to avoid retransferring problems like 1NT-2 -3 !-3 ?.

Seeking a major fit

There are apparent overlaps between major fit seeking conventions, especially Jacoby transfers with Stayman or Texas transfers. This section describes how to pick the best response.

Major two suiter, (54)+

To find the better fit, we consider the length difference between majors in our partnership. The opener's difference is at most 2, so our basic strategy is

However, with a weak hand, it is more important to keep the bidding low. We transfer to our longer major and then pass.

Same lengths, 55+

We choose the hearts from a weak two suiter for a chance to run out to 2 unless spades are sufficiently better.

Difference 1–2, (54)+

Major single suiter, 6+

Minor transfer

With an invitation or a game force without slam interest, we only show minor suits with a singleton or void.

We use fragment bids instead of Splinters here to avoid lead-directing doubles.

Competitive bidding

Competition does not affect auctions at 3NT and above.

Over (Dbl)

We keep things simple over a strong double (10+ HCP). Everything is natural.

Over (2 )

We play systems on over 1NT-(2 ). Most bids keep the same meaning. This is because 2 is so low that we can treat it as (mirrored) (1 )-1NT.

We recommend Leaping Michaels over a sole anchor suit. Take natural clubs for example.

The real headache is when (2 ) shows both majors e.g. Landy. We recommend reverse unusual vs. unusual.

Note that we pass when we can penalize both majors. A delayed double is for penalty since a takeout can usually penalize the other major.

Over (2 )

We play Transfer Lebensohl against overcalls 2 .

Over (2NT)

We have a special unusual vs. unusual structure over 1NT-(2NT) because we have not yet shown a suit.

The 2 opening

Our 2 opening is heavily influenced by Precision Club and Polish Club.

Multi 2

Our Multi 2 shows a 6-card weak two of either major.

Exactly 5-card weak twos

Weak twos in this bidding system show exactly 5 cards in the bid major and an unspecified suit. Multi 2 already takes care of 6+ cards.

Non-jump new suits are non-forcing because sometimes we need to escape from a certain misfit. With a strong misfit and a lower-ranking suit, we tend to buy 3NT with a minor suit. Otherwise, we go through 2NT and try to introduce hearts in the next round.

Unusual 2NT opening

The unusual 2NT opening is a preempt with 55+ in minors.

We advise against opening 2NT for (30)55 in the first two seats.

BTU 4-level preempts

In National Taiwan University Bridge Club (BTU), we use a 4X scheme that conveys approximately 0.58 more bits than traditional or Meckwell Namyats.