Natural 1♥♠
Modern bidding systems often require 5+ cards to open in a major. This is somewhat conventional because usually a 4-card suit is biddable in bridge, but this greatly improves search of 5-3 and 6-2 major fits.
Although minor openings are lower and more frequent, major openings are explained first because
- Major openings are more symmetric where both require 5+ cards.
- There are fewer mediocre exceptional bids which are difficult for beginners.
- Some conventions designed for majors can also apply to minors.
Light openings
Opening a major at the last 2 seats requires only 11+ HCP and 5+ cards, or just 10 HCP with 5-5 shape.
Nevertheless, a weak 2 can be made with only 5 cards at a non-unfavorable 3rd seat. This phenomenon excludes Drury from the Wbridge5 bidding system because major openings at the 3rd seat are seldom light.
Probing Wbridge5 5.12 shows that at unfavorable vulnerability the 3rd seat is not light at all: with 5 hearts and 10–11 HCP it opened 1♥ on 20 of 62 hands and passed the rest. See 3rd-seat weak 2s.
Responses to 1♥
The 1NT response is a semiforcing dustbin, and new suits at the 2-level are forcing 2/1. The strength of the preemptive 4♥ depends on vulnerability.
| 1♥ - | |
|---|---|
| 1♠ | 6–16, 4+♠ |
| 1NT | Semiforcing, 6–11 HCP, no other suitable call |
| 2♣♦ | 2/1, 12+, 4+# |
| 2♥ | 6–10, 3+♥ |
| 2♠ | SJS, 17+, 4+♠ |
| 2NT! | Special 2NT, 11–16, 3+♥, 2+ cards in each suit |
| 3♣! | Bergen mixed raise, 9–10, 4+♥ |
| 3♦! | Bergen LIM, 11–12, 4+♥ |
| 3♥ | Bergen PRE, 6–8, 4+♥ |
| 3♠! | SPL, 12–16, 0–1♠, 4+♥ |
| 3NT! | Serious 3NT, 16–19, 4+♥, 2–3 cards in each side suit |
| 4♣♦! | SPL, 12–16, 0–1#, 4+♥ |
| 4♥ | PRE, 0–8− HCP, 5+♥ |
Adjusted responses by a passed responder
Responses from a passed responder are no longer forcing because the previous pass has limited the strength. Some conventions are cancelled to make these bids passable.
| P - 1♥ - | |
|---|---|
| 2♣♦ | 11–12, 5+# |
| 2♠! | Fit-showing, 10–12, 5+♠, 3+♥ |
| 3♣♦! | Fit-showing, 10–12, 5+#, 3+♥ |
| 3♥ | LIM, 10–12, 4+♥, no singleton or void |
Probing Wbridge5 5.12 shows that a passed responder still splinters with shortness, so the limit raise denies it.
Responses to 1♠
The 1NT response is a semiforcing dustbin, and new suits at the 2-level are forcing 2/1. The strength of the preemptive 4♠ depends on vulnerability.
| 1♠ - | |
|---|---|
| 1NT | Semiforcing, 6–11 HCP, no other suitable call |
| 2♣♦ | 2/1, 12+, 4+# |
| 2♥ | 2/1, 12+, 5+♥ |
| 2♠ | 6–10, 3+♠ |
| 2NT! | Special 2NT, 11–16, 3+♠, 2+ cards in each suit |
| 3♣! | Bergen mixed raise, 9–10, 4+♠ |
| 3♦! | Bergen LIM, 11–12, 4+♠ |
| 3♥ | SJS, 17+, 7+♥; or 15+, 4+♠ 4♥, no minor longer than 3 |
| 3♠ | Bergen PRE, 6–8, 4+♠ |
| 3NT! | Serious 3NT, 16–19, 4+♠, 2–3 cards in each side suit |
| 4♣♦♥! | SPL, 12–16, 0–1#, 4+♠ |
| 4♠ | PRE, 0–8− HCP, 5+♠ |
Probing Wbridge5 5.12 shows that 3♥ over 1♠ is also a strong raise with 4 hearts. Of 300 hands with 4–5♠ and 17–24 HCP, 50 bid 3♥, all with exactly 4♥, 1–3 cards in each minor, and 17–22 HCP; for example, ♠AJT2 ♥KQ53 ♦AQ2 ♣Q8. Random hands add ♠AKQ2 ♥AQT8 ♦J7 ♣973 and ♠AQ63 ♥QT64 ♦AK7 ♣J8.
Adjusted responses by a passed responder
Responses from a passed responder are no longer forcing because the previous pass has limited the strength. Some conventions are cancelled to make these bids passable.
| P - 1♠ - | |
|---|---|
| 2♣♦♥ | 11–12, 5+# |
| 3♣♦♥! | Fit-showing, 10–12, 5+#, 3+♠ |
| 3♠ | LIM, 10–12, 4+♠, no singleton or void |
Preemptive raise to the 4-level
Such raise directly jumps to game, showing at most 8− HCP and usually 5+ support. Its minimum strength is determined by vulnerability.
- Unfavorable: 10+
- Both vulnerable: 10+
- None vulnerable: 8+
- Favorable: 7+
Major raise structure
The 12 points are intentionally duplicated in this table. It is difficult to find clear-cut game-forcing hands with only points.
With a flat hand, 3-card support, and 6 or 11 HCP, Wbridge5 bids 1NT for better continuations.
| 3-card support | 4+-card support | |
|---|---|---|
| 6–8 points | 2M, 1NT | 4M, 3M, 2M |
| 9–10 points | 2M | 4M, 3♣ |
| 11–12 points | 2NT, 1NT, 2M | 4M, 3♦ |
| 12–16 points | 2NT, 2/1 | 2NT, Splinter |
| 16–19 points | SJS, 2/1 | 3NT, SJS, 2/1 |
| 20+ points | SJS, 2/1 |
Choice of new suit
- Choose the longest suit.
- To break a tie, bid the cheapest call for 4-4, the highest suit for 5-5 or above.
In the following examples, your partner opened 1♥ and you have not passed.
- ♠J1064 ♥A8 ♦A4 ♣108763: Bid 1♠. This hand is too weak to bid 2♣.
- ♠AK3 ♥K6 ♦J652 ♣AK53: Bid 2♣. Bid the cheapest call for 4-4.
- ♠Q9 ♥6 ♦Q9743 ♣AK942: Bid 2♦. Bid the highest suit for 5-5.
- ♠A103 ♥A953 ♦AQ9 ♣AK3: Bid 2♣. This hand is too strong for 3NT. Probing Wbridge5 5.12 shows a 3-card minor bid with such a blockbuster: 2♣ on 272 of 300 boards and 2♦ on the rest.
Special 2NT
The special 2NT shows
- Limit raise or better without slam interest (11–16 points, 3+ support).
- Somewhat balanced (2+ cards in every suit).
If responder has passed, this 2NT bid has given enough information for opener to sign off.
Puppet special 2NT
If responder has not passed yet, this 2NT bid is a puppet forcing opener to bid an artificial relay 3♣. Responder shows support and strength in the second round.
Probing Wbridge5 5.12 shows that opener splinters instead of relaying with 17+ points and a singleton or void. See constructive rebids.
The 3♥ response is also forcing to game because Bergen 3♦ already takes care of invitational hands.
| 1M - 2NT! - 3♣! - | |
|---|---|
| 3♦! | Minimum short, INV+, 11–14, 3=M |
| 3♥! | Minimum long, FG, 12–14, 4+M |
| 3♠! | Maximum long, FG, 14–16, 4+M |
| 3NT! | Maximum short, FG, 14–16, 3=M |
This convention appears to be Wbridge5’s own, probably derived from Jacoby 2NT. It relieves the 2/1 structure of Wbridge5 in three ways.
- Special 2NT handles 3-card limit raise, freeing dustbin 1NT from forcing.
- Jacoby 2NT fits into special 2NT and serious 3NT, leaving no burden for other bids.
- Responder shows. Opener relays, hiding information from opponents.
Not probed
- The preemptive 4♠ raise by vulnerability: only the 4♥ raise was probed at all four vulnerabilities.
- Light 1♠ openings in the 3rd and 4th seats away from none vulnerable: only hearts were probed at the other vulnerabilities.
- The 3♥ response to 1♠ with 4♥ below 17 HCP (two random hands), and the auction after it.