He played five shifts, totalling nearly four minutes, before heading to the dressing room. The Sabres ruled him out for the rest of the game.
Afinogenov, with eight goals and 11 assists, entered the night tied with Atlanta's Marian Hossa for second in scoring in the NHL. He had points in nine of Buffalo's first 13 contests and was on a three-game scoring streak before Saturday's game against the Maple Leafs.
He led the Sabres last season with a career-high 73 points, including 51 assists.