If you played 1♦ - 2♦ as a raise showing 6-10 Support Points for diamonds, and you played 1♦ - 3♦ as an invitational diamond raise, how would you show a game forcing diamond raise?
After a 1♥ or 1♠ opening, it is common to use an artificial 2NT response (Jacoby 2NT) as a game forcing raise. That isn’t practical after a minor suit opening because notrump is your preferred game if a major suit fit isn’t available. Inverted Minor Raises were invented to give responder a convenient way to show an invitational or better raise for opener’s minor.
Meaning of an Inverted Minor Raise:
- 1♣ - Pass – 2♣ is forcing, showing 11+ Support Points, 5+ clubs, denying a 4-card major
- 1♦ - Pass – 2♦ is similar, but shows 4+ diamonds (It is rare to open 1♦ with just 3 diamonds)
After the inverted minor raise, opener rebids naturally, but 2♥/♠ don’t guarantee length. They are forcing and show stoppers. If either partner bids 3 of opener’s minor, they are saying they are willing to stop there (i.e. responder has just an invitational hand, or opener is saying they would decline a game invitation). Other bids are forcing. Bids above 3 of opener’s minor are game forcing.
Many teachers recommend playing a 2NT rebid as non-forcing. The problem with this approach is opener cannot bid 2NT with a hand which would accept an invitation to game. Opener must either jump to 3NT or manufacture a bid. Opener’s jump to 3NT consumes a lot of room. Over a forcing 2NT rebid, responder has the room to show their shape. This allows for a better assessment of whether a slam is available. Over a jump to 3NT, a strong responder must guess at the 4-level. To avoid obstructing your own auctions, we recommend playing an Inverted Minor raise as forcing to 3 of opener’s minor. This allows opener to make a descriptive 2NT rebid even if they would accept an invitation to game. Opener’s jump to 3NT shows a balanced 18-19 HCP hand with a 3-card minor.
Playing Inverted Minors, it is common to play a jump raise of opener’s minor as preemptive.
- 1♣ - Pass – 3♣ shows a weak hand with 5+ clubs and no 4-card major
- 1♦ - Pass – 3♦ shows a weak hand with 5+ diamonds and no 4-card major
The problems with this approach include:
- forcing a strong opener to guess after the weak jump raise
- responder has no way to show a raise with 7-10 Support Points
Since there isn’t much need to preempt the auction when your partner has an opening hand, it is better to use a jump raise to show a Mixed Raise.
- 1♣ - Pass – 3♣ shows 7-10 Support Points, 5+ clubs, & no 4-card major ♠84 ♥Q4 ♦A762 ♣Q9863
- 1♦ - Pass – 3♦ shows 7-10 Support Points, 4+ diamonds, & no 4-card major ♠874 ♥Q4 ♦A762 ♣Q963
A Mixed Raise allows you to find games which might be missed if responder bids 1NT, hiding their trump support. See the "Mixed Raises Part 2" article by Steve Weinstein and Dan Wolkowitz to learn more about replacing the Inverted Minor preemptive raise with a Mixed Raise.
Your game priorities after an inverted minor raise is 3NT if viable. Otherwise, play in 4♥ or 4♠ in a 4-3 fit if viable. Your games of last resort are 5♣ or 5♦ because they require 11 tricks and pay just 20 points per trick.
If you play splinter bids, they apply after an inverted minor raise. An immediate splinter by responder (e.g. 1♣ - Pass – 3♠) is stronger than a delayed splinter (e.g. 1♦ - Pass – 2♦ - Pass; 2♥ - Pass – 3♠)
Inverted Minor raises are typically off after an overcall or a takeout double.