Five-card majors

Five card majors is a contract bridge convention which is very powerful and standard in modern bidding systems today , including Standard american and Bridgebase basic.

The Concept

Typically when a bridge player makes a natural bid, he is promising at least 4 cards in that suit and asking partner if it will be an advantageous trump suit for the partnership. Because of the power of naming a trump suit with an 8-card fit, the responder with 4 more cards of that suit will support his partners bid as if to say "we have found are 8-card fit, and so what is next."

With 13 cards in each suit, an 8-card fit implys that only 5 remaining trump cards can be help by the opponents. They will mose likely be distributed 3-2 among the opponents, so pulling trump for three rounds will probably remove all trump cards from the opponents and leave 2 addditional trump to be used separately for offensive purposes. However if the opponents trump cards are distributed 4-1 or 1-4, then pulling trump will result in no trumps left for offensive purposes.

The value of 5-card majors can be understood then on two levels:

• When partnerships have a 5-3 distribution in a major suit (hearts or spades), then the 8-card fit in a major suit is easier to find for the player with only 3 cards in the major suit. The strong preference to play contract bridge in the major suits at the game level makes the 5-card major convention very attractive.
• When the trump suit can be declared with a 5-3 fit, then often 1 extra trick has be had due to the extra trump card in declarer's hand because
  • if the opponents 5 trump cards are distributed 3-2 or 2-3, then declarer will have two trump cards to used offensively.
  • if the opponents 5 trump cards are distributed 4-1 or 1-4, then declarer can pull trump for 4 rounds, not wasting all of dummys trump, and saving 1 trump card in declarers hand for offensive purposes.

To Play 5-card Majors

Both partners must agree to follow the 5-card major bidding convention on their opening bid. You must have at least 5 cards in hearts or spades to open the bidding with that suit. Responser is expected to show support with 3 matching cards, indicating an 8-card fit. With only 4 cards in a major suit, the opening bidder is expected to open one in the best minor suit, and then rebid the 4 card major at the next opportunity. After any first bid by partners or opponents, the 5-card limitation is done, and any other bid is typically promising only 4 cards as before. Bridge partnerships who use five card majors also typically use the weak 1 club bid, which does not promise 4 clubs, and is used as a default opening bid to indicate that opener has:

• at least 13 high card points and interest in winning the bid,
• no 5-card major (else opener would have bid it),
• no 4 diamonds (else opener would have bid them),
• no 4-4 distribution in the majors (else opener would have opened 2 diamonds).

References

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