Muiderberg convention

Muiderberg is a bidding convention in the card game bridge. It is a two-level preemptive opening based on a two-suiter with precisely a five-card major and a minor suit (four-card or longer). In Muiderberg the 2{{Hearts}} opening denotes five hearts and an unknown minor suit, whilst 2{{Spades}} denotes five spades and an unknown minor suit. The convention is also known as the Dutch Two, Lucas Two or Woo Two (mainly UK) opening.{{cite web |url=http://www.bridgeguys.com/Conventions/muiderberg_muiderbergh.html |title=Muiderberg |website= Bridge Guys |accessdate= 7 November 2015 }}

__NOTOC__

The convention is named after the Dutch village Muiderberg, the residence of the designers of the convention – Onno Janssens and Willem Boegem.{{OEB|7|282}}

Responses

The partner of the Muiderberg opener can take the following actions:

  • pass (with tolerance for the opened suit)
  • bid 3{{Clubs}} (a pass-or-correct bid)
  • bid 3{{Diams}} to invite for game in the major suit
  • bid 2{{Spades}} (over 2{{Hearts}}) as a contract improvement (opener is allowed to raise with a suitable hand)
  • bid 3{{Hearts}}/{{Spades}} (opener's suit) as a preemptive raise
  • bid 3{{Spades}}/{{Hearts}} (other major) which is non-forcing but invitational
  • ask for the minor suit using a 2NT relay bid with a strong hand.

The 2NT response is often defined as forcing to game, for example in Biedermeijer and AcolPlus. In particular, with a strong hand with a good suit of its own or with support for partner's opened suit, responder must bid 2NT first, as there is no other way to establish a force. The Muiderberg opener can respond in several ways to the 2NT answer:

  • bid 3{{Clubs}} with a minimum and clubs / with four clubs
  • bid 3{{Diams}} with a minimum and diamonds / with four diamonds
  • bid 3{{Hearts}} with a maximum and clubs / with five or more clubs
  • bid 3{{Spades}} with a maximum and diamonds / with five or more diamonds
  • bid 3NT with 4-4 in both minors
  • bid 4{{Clubs}}/{{Diams}} with a 6+ cards in the bid suit

Both approaches (2NT forcing to game or forcing for one round only) are equally popular.

In competition, 3{{Clubs}} is natural (opener is expected to pass) while 2NT asks for opener's minor suit and is not necessarily strong. Further, 4{{Clubs}}/{{Diams}} are defined as fit-bids in competition.

Variants

Partnerships may choose to play Muiderberg Twos (or the variants below) as: (a) at least 5-4 shape, (b) at least 5-5 shape, or (c) at least 5-4 when non-vulnerable but at least 5-5 when vulnerable, for added safety. Statistically, 5-4 hands are about four times as common as 5-5.

A variant known as Lucas Twos allow for five cards or more in the bid suit (diamonds, hearts or spades) and four cards or more in a second suit which can be any of the remaining three suits. Particularly in the UK, the term Lucas Two is often used to describe what is actually a Muiderberg Two, where the second suit has to be a minor; this makes it safer for responder to explore for a second-suit fit if short in opener's longest suit.

A difficulty with Muiderberg and Lucas Twos is that it is no longer possible to make a Weak Two bid with a single-suited major. These hands may instead be bid using the Multi 2 diamonds convention.

Another variant, called Antispades Twos, provides for either a two-suited hand containing at least nine cards in the two suits with four or more cards in the bid suit — clubs, diamonds or hearts — and four or more in another suit, or a single-suited hand of at least six cards in the bid suit, in a hand worth 5–10 HCP.

See also

References

{{reflist}}

{{DEFAULTSORT:Muiderberg Convention}}

Bibliography

  • {{cite book|last1=Wilson|first1=Gavin|title=Antispades Twos — Open Markedly More Often|date=2016|publisher=Org2B Press|location=Claygate, Surrey, UK|asin=B01MRUJ8AA}}

{{WPCBIndex}}

Category:Bridge conventions