Iancu - Agica system notes
♣ ♦ ♥ ♠
Introduction
This document aims to provide a complete explanation of the MOSCITO bidding system used by Stefan Iancu and Bogdan Agica. It is mainly based on Richard Willey’s and Paul Marston’s system old-notes, which have provided invaluable help.
The MOSCITO bidding system was designed to support a “Quick in - quick out” auction style. We find that placing most hands in a playable contract as quickly as possible is providing a significant tactical advantage.
Most constructive bidding is based on relays, which are designed to make the unknown hand the declarer in ~90% of the time. It’s anchored by a strong club (15+ HCP) opening, which makes room for light, constructive and descriptive opening bids.
Transfer opening bids are used (1♦ → ♥, 1♥ → ♠, 1♠ → ♦), in order to ensure the comparatively well-defined hand is exposed in the dummy.
Opening bids
Balanced hands open at least 10HCP, only with lead directing purposes. Adjustments for wildly unbalanced hands will be taken into account, e.g. Kxxxx / Kxxxxx / xx / - is an opening hand.
| Opening bid | Meaning | 3rd/4th Position |
|---|---|---|
| 1♣ | 15+ HCP, any distribution | 17+ HCP, any distribution |
| 1♦ | 4+♥, ♥>♠, 8-14 HCP | 10-16 HCP |
| 1♥ | 4+♠, ♠>♥, 8-14 HCP | 10-16 HCP |
| 1♠ | 4+♦, either 6♦, or 5-4 minors, could have 6♦4M | 10-16 HCP |
| 1NT | 12-14 BAL or SEMIBAL, no 5+M | 13-16 HCP |
| 2♣ | 6+♣, could have 4M, 8-14 HCP | 10-16 HCP |
Limited opening bids
1♦
The 1♦ opening bid promises at least 4 ♥, hearts longer than spades, and roughly 8-14HCP. It could be balanced, with at least 10 HCP...
Raise structure:
| Bid | Meaning |
|---|---|
| 4♥ | To play. Could be anything. |
| 4♦, 4♣, 3♠ | SPL, 4+H |
| 3♥ | Value raise. 6-10HCP, 4+H, good ODR |
| 3♦, 3♣, 2NT | Fit-showing jumps. 4+♥, 5+suit (2NT → ♠) |
| 2♥ | 3+♥, 6-10HCP, 4♥ if low ODR |
Other bids:
| 2♠ | INV, 5+♠, 5+m |
| 2♦, 2♣, 1NT | NAT, NF |
| 1♠ | NAT, F1 |
| 1♥ | Relay |
Relay structure:
1♦ - 1♥:
| Bid | Meanings | |||||
|---|---|---|---|---|---|---|
| 1♠ | 0-3♠, BAL or 3SUIT or 5♥ + 4+♣ | |||||
| 1NT | 44♥♠ BAL or 3SUIT | Relay | ||||
| 2♣ | ♥+♦ | Relay |  |
|||
| 2♦ | ♥ 1SUIT | Relay | |
|||
| 2♥ | Reverser 4♥ + 5+♣ | Relay | Reverser 4♥ + 5+♦ | |
||
| 2♠+ | ♥+♠ 2suit | Relay → 2SUIT | →1SUIT | 55♦+♥, etc | |
|
| 2NT+ | BAL (2NT 5332, 44♦♥, 2434, 3424) | |||||
1♥
The 1♥ opening bid promises 4+♠ , spades longer than hearts, and roughly 8-14 HCP.
Raise structure:
| Bid | Meaning |
|---|---|
| 4♠ | To play. Could be anything. |
| 4♣♦♥ | SPL |
| 3♠ | Value raise. 4+♠, ~6-10HCP, good ODR |
| 3♣♦♥ | FSJ. 5+ cards, 4+♠, INV |
| 2♠ | 3+♠, ~6-10HCP. Low ODR if 4♠ |
Other bids:
| Bid | Meaning |
|---|---|
| 2NT | INV, 5+♥ + 5+m |
| 2♣♦♥ | NAT, NF |
| 1NT | NAT, NF |
| 1♠ | Relay |
Relay structure after 1♥ - 1♠:
| Bid | Meanings | ||||
|---|---|---|---|---|---|
| 1NT | BAL or 3SUIT or 5+♠ 4+♥ | ||||
| 2♣ | ♠+♦ 2SUIT | Relay | |||
| 2♦ | 5+♠ 4+♣ 2SUIT | Relay | BAL | ||
| 2♥ | Reverser 4♠ + 5+♣ | Relay | Reverser 4♠ + 5+♦ | 3SUIT with ♥ shortage | |
| 2♠+ | ♠ 1SUIT | Relay → 2SUIT | ♦+♠ 2SUIT | 5+♠ 4+♥ 2SUIT | |
Three-suited hands with minor shortage
There are two patterns to worry about (5=4=0=4 and 5=4=4=0). They are resolved with a 3NT bid, either through 2NT (high shortage) for 5=4=0=4, or directly for 5=4=4=0. The 7-4-2-0 distribution is therefore displaced a step.
Balanced hands
Balanced hands are shown with a 1♥ - 1♠(R) - 1NT - 2♣(R) - 2♦ development. After the 2♥ relay, the whole structure is downshifted a step, due to the lack of 4♥ in opener’s hand. Thus:
| Bid | Meaning |
|---|---|
| 2♠ | 5332 |
| 2NT | 4♦4♠(32) |
| 3♣ | 4=2=3=4 |
| 3♦ | 4=3=2=4, zoom |
1♠
The 1♠ promises at least 4+♦, either 5-4 minors either way, or 6+♦, and roughly 8-14HCP. It could hold 6+♦ + 4M.
Raise structure
| Bid | Meaning |
|---|---|
| 3♥, 3♠, 4♣ | SPL, 4+♦ |
| 3♦ | Value raise, ~6-9 HCP, 4+♦ |
| 3♣ | P/C to better minor |
Other bids
| Bid | Meaning |
|---|---|
| 2NT | |
| 2♥, 2♠ | NAT, NF, 6+ cards |
| 2♦ | 5+♠, F1 |
| 2♣ | 5+♥, F1 |
| 1NT | Relay, not necessarily strong |
Relay structure
The 1NT response to 1♠ is F1, however not necessarily strong. After that:
| Bid | Meanings | ||
|---|---|---|---|
| 2♣ | 5-4 minors | ||
| 2♦ | 6+♦ | To play | |
| 2♥ | 6+♦ + 4♥ | Relay | Relay |
| 2♠ | 6+♦ + 4♠ | → 1SUIT | → 2SUIT |
1NT
The 1NT opening bid promises 12-14HCP and a BAL or SEMIBAL distribution. It cannot contain a 5M. The system is fairly relaxed on whether to open 1NT with 1 or 2 4M.
Choosing whether to open 1M or 1NT
With a good 4M, especially with a small doubleton, it’s advisable we open 1♦ or 1♥. Always open 1NT with 4333.
Response structure
2♣
The 2♣ opening bid promises 6+♣, 0-3♦, 0-4M, and roughly 8-14 HCP.
Response structure
| Bid | Meanings | |
|---|---|---|
| 2D | Relay | |
| 2♥, 2♠ | F1, NAT | 6+♣ + 4M |
| 2NT | BAL, INV | → 1SUIT |
| 3,4,5♣ | PRE | |
1♣ opening bid
The 1♣ opening bid is the cornerstone of the system. It shows ~15+ HCP (~17+ HCP in 3rd/4th POS). We tend to upgrade very distributional hands, and to downgrade bad balanced hands.
The response structure is based on a negative 1♦ response and transfer canape responses. Any step that is omitted denies the actual significance of that step. E.g. 1♣ - 1♠ (4+♥, UNBAL, POS) denies the significance of 1♣ - 1♥ (4+♠, UNBAL, POS), therefore implies 0-3♠.
Response structure
| Bid | Meaning | ||
|---|---|---|---|
| 1♦ | Negative, 0-7HCP or 0-1CTRL, any distribution | ||
| 1♥ | 4+♠, UNBAL, could have longer suit, could be 3SUIT with ♥+♠+m | ||
| 1♠ | 4+♥, 0-3♠, UNBAL, could have longer suit | Relay | |
| 1NT | Any BAL, POS (4333, 4432, 5332) | Relay | 4+♥, 4+♠, 2SUIT or 3SUIT |
| 2♣ | 4+♦, either 1SUIT, or 3SUIT with ♣+♦+M | 4+♥, 4+♦, 2SUIT | 4+♠, 4+♦, 2SUIT |
| 2♦ | 6+♣, 1SUIT | 6+♥, 1SUIT | 6+♠, 1SUIT |
| 2♥+ | ♣ + ♦, 2SUIT | 4+♥, 4+♣, 2SUIT | |