This part shares similarities with the 1♣ opening.
There are also differences because 1♦ shows a long suit that allows further
preempts.
- Notrump transfers to clubs as its natural meaning is not very useful.
- Unlike 1♣ (X), there is no space for Transfer Walsh here.
- Reuse 1♦ (X) 2♣ for Flannery because the rebidding problem persists.
| 1♦ (X) | |
|---|
| XX | NF BAL G/T, 10+ |
| 1M | F, 7+, 4+# |
| 1NT! | TRF, 7+, 5+♣ |
| 2♣! | ART, 5–11, 5+♠, 4+♥ |
| 2♦ | PRE, 0–7, 4+♦ |
| 2M | PRE, 0–7, 6+# |
| 2NT! | TRF: (PRE, 7+♣) or (FG, 6+♣) |
| 3♣! | INV+ TRF, 4+♦ |
| 3♦ | CONST, 8–10, 4+♦ |
| 3M | PRE, 7+# |
| 1♦ (1♥) | |
|---|
| X! | TRF, 7+, 4+♠ |
| 1♠! | TRF to 1NT, 8+ |
| 1NT | NAT, 8–10 |
| 2♣ | F, 10+, 5+♣ |
| 2♦ | CONST, 6–9, 4+♦ |
| 2♥! | TRF, 6+♠ |
| 2♠! | INV+, 10+, 4+♦ |
| 2NT | NAT INV, 10–11 |
| 3♣ | PRE, 7+♣ |
| 3♦ | PRE, 0–6, 4+♦ |
| 3♥! | TRF: (PRE, 7+♠) or (FG, 6+♠) |
| 3♠! | Gambling, SOL 7+♣ without stopper |
| 1♦ (1♠) | |
|---|
| X! | NEG, 7+, (4–5♥ or BAL FG) |
| 1NT | NAT, 8–10 |
| 2♣ | F, 10+, 5+♣ |
| 2♦! | TRF, 10+, 5+♥ |
| 2♥ | NF, usually 6+♥ |
| 2♠! | CONST+, 8+, 4+♦ |
| 2NT | NAT INV, 10–11 |
| 3♣♥ | PRE, 7+# |
| 3♦ | PRE, 0–7, 4+♦ |
| 3♠! | Gambling, SOL 7+♣ without stopper |