The G1 Climax 31 was a professional wrestling tournament promoted by New Japan Pro-Wrestling (NJPW). The tournament commenced on September 18 and concluded on October 21, 2021. It is the thirty-first edition of G1 Climax, and forty-seventh edition of the tournament counting its previous forms under different names. B block winner Kazuchika Okada defeated A Block winner Kota Ibushi by referee stoppage after Ibushi suffered an arm injury when he attempted to perform a Phoenix Splash on Okada, forcing referee Red Shoes Unno to stop the match.