No. 650

Black to play. Praggnanandhaa–Salimova, April 2021. White’s last move, Bg2-f3, was a blunder. Which move should Black play to exploit it? Email answers to chess@spectator.co.uk by Monday 26 April. There is a prize of £20 for the first correct answer out of a hat. Please include a postal address and allow six weeks for prize delivery.

Last week’s solution 1 Rxd5! set up a queen trap: exd5 2 g3! Qh3 (2…Qxh5 3 Nf6+) 3 Bf5 Kf8 4 Nxh6 and Black resigned. Less effective are 1 Qd3 f5! 2 exf6 Qxg4, or 1 Rd4 Kf8! 2 Nh2 Rc1+!
Last week’s winner David Forbes, Ellon, Aberdeenshire