Roman Jump Overcalls

Roman Jump Overcalls (RJOs) are two-suited overcalls that jump into the cheaper (not lower-ranking) of the two suits shown. They show four or more cards in the higher-ranking (not cheaper) suit and five or more cards in the lower-ranking suit. They are nominally 5-7 AKQ loser hands in strength, although 2-level jumps at favorable vulnerability can be shaded. To be complete, the system uses 2NT and the direct cue bid to show two-suited hands as well. Cue bids are the suits above and below (not top and bottom) their suit; 2NT shows the nontouching suit (e.g. spades over diamonds) with fewer than 5 losers. This is because the jumps are semi-natural and non-forcing.
Over 1C:
2C: = 4+ spades and 5+ diamonds, 7 or fewer losers
2D: = 4+ hearts and 5+ diamonds, 5-7 losers
2H: = 4+ spades and 5+ hearts, 5-7 losers
2S: = natural, weak
2NT = hearts and another, fewer than 5 losers
Over 1D:
2D: = 4+ hearts and 5+ clubs, 7 or fewer losers
2H: = 4+ spades and 5+ hearts, 5-7 losers
2S: = 4+ spades and 5+ clubs, 5-7 losers
2NT = spades and another, fewer than 5 losers
Over 1H:
2H: = 4+ spades and 5+ diamonds, 7 or fewer losers
2S: = 4+ spades and 5+ clubs, 5-7 losers
2NT = clubs and another, fewer than 5 losers
3C: = 4+ diamonds 1 and 5+ clubs, 5-7 losers
Over 1S:
2S: = 4+ hearts 1 and 5+ clubs, 7 or fewer losers
2NT = diamonds and other, fewer than 5 losers
3C: = 4+ diamonds 1 and 5+ clubs, 5-7 losers
3D: = 4+ hearts 1 and 5+ diamonds, 5-7 losers

1 Jumps to the three-level or ones that force to the three-level pretty much always show 5-5 shape or better.

Jumps higher than listed above are natural and preemptive.

Followups

After the 2NT overcall, the cue bid is probing and game forcing, usually has no slam interst. The lower suit usually promises 3 or more cards in it and no game interest. The anchor suit is the same. The upper suit is artificial and game forcing with slam interest. Rebids are natural. Some partnerships play that this bid initiates a relay structure, but this is so uncommon that it's only worthwhile in the most frequent of partnerships. 3NT is natural and to play. Jumps below game agree the anchor suit and show shortness. Jumps to game are natural. 4NT is RKCB in the anchor suit; 5NT is GSF in the anchor suit.

After RJOs, 2NT is an artificial game try with three cards in the highest-ranking suit. Raises are blocking, usually following the law of total tricks. Cue bid is a strong game invitation, but does not promise a rebid. A bid of the fourth suit is to play. A jump cue promises game-going values and sets up a force; a jump to game does not.

After the cue bid, continuations are similar; cue is a strong invitation/probe, jumps are blocking, and 2NT is a game try with 3 cards in the higher-ranking suit.

With wild shape, two-suited bidders are allowed to bid again, but generally don't unless they have a good reason.

Advancer should usually give up on slam and bounce to game unless he has a mountain after an RJO. Bidding game on the first round of the auction puts an enormous amount of pressure on the opponents and often leads to a won board (assuming it's a sensible choice).

After a cue or RJO is doubled, pass is to play. Redouble is primarily for blood after an RJO, but says, "you choose" after a cue.

These bids still apply by passed hands, although the 2NT bid is very rare, showing freak distribution, typically 7-5 or so.

Doubles by advancer are card-showing, hands with no clear direction.

Red on white, 7-loser hands are uncommon. Raises are somewhat invitational.

Choices

Bids that force to the three-level should really show decent hands, usually 5-5, sometimes 6-4. White on red, however, all bids have been known to be stretched a little.

If one has a fragment in the fourth suit, generally it's right to make a takeout double (or NTO) unless the two suits are chunky and the fragment is three small. This can be stretched a bit if the two suits are majors; it's often right to show two decent majors even with honor third in the other minor.

When the choice is between a two-suited bid and a power double, more factors enter into the choice. With 5431 hands, strongly tend to pick the two-suited action. With 5422, judge by honor location. If the two short suits are strong and there's a double stop in their suit, it's likely to be right to make a power double.

What do you do with a normal weak jump overcall? Either make a simple overcall or preempt one level higher, depending on the suit and your personality and methods.

When on lead, it's often right to lead the back suit (the four-card one shown) because partner will not often show both suits with a good five-card suit and a very weak four-card suit.


Jeff Goldsmith, jeff@tintin.jpl.nasa.gov, Dec. 22, 1997