What are Checkback Stayman and XYZ?
When opener rebids 1NT, conventions like Checkback Stayman use an artificial 2♣ bid to ask opener if they have 3-card support for responder's major.
A common bidding problem arises when the auction starts: 1♣ – 1♠ – 1NT. Responder has a 5-card Spade suit and an invitational hand (11 points), but they don't know if Opener holds 2 Spades or 3 Spades. If responder rebids 2♠, it is a weak sign-off. If responder jumps to 3♠, it is game-forcing.
To solve this, partnerships use Checkback Stayman (or a modern variant called XYZ). Over Opener's 1NT rebid, Responder bids an artificial 2♣. This asks Opener: "Do you have 3-card support for my major? Do you have an unbid 4-card major?"
Why Checkback Stayman works
Finding a 5-3 major suit fit is vital. Because Opener's 1NT rebid promises a balanced hand, they could easily hold 3-card support for Responder's major.
Using 2♣ as an artificial relay keeps the bidding low. It forces Opener to describe their hand further. Opener will bid 2 of Responder's major with 3-card support, bid the "other" major if they hold 4 cards there, or bid 2♦ to deny either feature.
A worked example: Finding the 5-3 fit
Your Hand (Responder):
♠ A K 8 5 2
♥ K 4
♦ 9 5 3
♣ 8 4 2
(10 HCP, 5 Spades)
The Auction:
- Partner: 1♦
- You: 1♠
- Partner: 1NT
- You: 2♣ (Checkback Stayman)
- Partner: 2♠
Caption: You have 10 points and 5 Spades. You need to know if partner has 3 Spades. By bidding 2♣, you ask the question. When partner bids 2♠, they confirm 3-card support! You now know you have an 8-card fit. With an invitational 10 points, you can now invite game by bidding 3♠.
Four common mistakes
- Opener passing the 2♣ bid (Checkback Stayman is completely artificial and forcing!).
- Responder using Checkback Stayman without invitational values (you need at least 10/11 points because you are forcing the auction to the 2-level or 3-level).
- Jumping to 3 of your major instead of using Checkback, which takes up all the bidding space.
- Forgetting whether you agreed to play standard Checkback (2♣), Two-Way Checkback, or XYZ.
When the rule does not apply
If the opponents intervene in the auction (e.g., 1♦ – Pass – 1♠ – 2♥ – 2NT), Checkback Stayman is usually off. It applies in uncontested auctions where Opener rebids 1NT or 2NT.
Key takeaways
- Used after Opener rebids 1NT.
- Responder bids an artificial 2♣.
- Asks Opener for 3-card support for Responder's major.
- Asks Opener for an unshown 4-card major.