4^th suit forcing

It may or may not have occurred to you that it’s a bit of a waste of time having an auction like this...........

1ª 2§ 2© 3¨

Partner has opened and shown 2 suits, so the chances of you having a diamond fit are nil. Bidding the 4^th suit – Diamonds in this case is redundant.

So why not put it to better use and ask partner for more information about their hand.

Partner has opened 1ª and rebid 2© after your 2§

ª K4

©K86

¨9652

§AQ83

You can’t yet see a major suit fit of the magic 8 cards. It would be foolish to bid 3NT and lose the first 5 diamond tricks.

So – use the 4^th suit forcing (3¨) to ask for more information.

Partner may hold.....

ª AQ9862

©AQ73

¨J3

§3

When 4S is an excellent contract

Or

ª AJ1952

©AQJ106

¨A4

§9

When 4© is an excellent contract

Or

ª AQJ74

©A1097

¨K2

§106

When 3NT is an excellent contract but is best played by partner because then the ¨K is protected against the lead.

After you bid your 4^th suit, partner cannot pass it (that’s why it’s called 4^th suit forcing). Partner can show a 6^th card in 1^st bid suit, a 5^th card in 2^nd bid suit, or a stop for NTs in the 4^th suit, or even support your suit with 3 cards.

Most people play this as forcing to game.

Example hands and bidding sequences. 1.

West East

ª K54 ª AQ1062

©AK985 ©72

¨4 ¨J7

§Q1086 §AJ93

East could support clubs at their second bid, but that looks like a good way of getting a good score when any contract out of 3NT, 4©, or 4ª could be available.

1© 1ª

2§ 2¨(4^th suit)

2ª 4ª

Example hands and bidding sequences. 2.

West East

ª Q ª AK875

©AQ1065 ©94

¨AQ4 ¨75

§J852 §AQ63

Same auction as the last hand until West has to respond to the 2¨ force.

This time West has a nice ¨ stop to show and 3NT is a good contract to play from this hand.

1© 1ª

2§ 2¨(4^th suit)

3NT.

3NT may work if played by East but it is far less safe.

Example hands and bidding sequences. 3.

This one is perhaps a more controversial auction.

West East

ª J9 ª AQ10865

©A105 ©KQ94

¨A64 ¨5

§KJ852 §Q63

- 1ª

2§ 2©

3¨(4^th suit) 3ª

4ª

(Thoughts after the 2H bid)

If partner has a 6^th spade or a 5^th heart either major suit contract will be better than 3NT, but if they have nice diamonds (KJ4) then 3NT will be better.

There is nothing too wrong with bidding 3NT on the West cards but many would choose to use 4^th suit to try and find a better contract.

Priorities

Show 3 card support for partner’s Major suit.

Show a stop in the 4^th suit by bidding NTs.

Show extra length in one of your suits.

If the auction has developed something like 1ª - 2§ - 2©- 3¨ the person making the 4^th suit bid is unlikely to be interested in § support.

In particular the opener should beware of going beyond 3NT

but if there is nothing else to show,

they may have to.

¨©§ª