COMMITMENT TO CLAIMING A DISCARD WITH EXPOSURES (Article 177)

Commentary: When a player claims a discard and places it on the flat part of the rack or they expose tiles from their hand, they are committed to using it. If they expose the wrong tiles or number of tiles, they may correct their mistake—provided they have not performed a joker exchange or discarded. This rule applies as long as the tile they picked up is the actual discard.

Question from a Player: A player (who was next in line to play) called for a discarded tile. She placed it and three other tiles for display on her rack. When she proceeded to discard her unwanted tile but did not lay it down, she realized she did not want the claimed tile. She returned the “claimed” tile to the table, placed the other tiles back in her hand, and proceeded to draw another tile. her discarded tile had not yet touched the table. Is a tile laid, a tile played?

Answer from the NMJL: Once a tile has been called and placed on top of the rack, especially along with other tiles, the move cannot be undone.

Source: Mah Jongg Made Easy (2024 page 15 paragraph 1); National Mah Jongg League Bulletin (2023)