Gleyber Torres, the Yankees’ star second baseman, prompted an audible gasp from the crowd when his right leg buckled while fielding a grounder and made an early exit Friday night as the host Yankees lost to the Toronto Blue Jays, 4-3.

Torres said his lower legs felt weakness. Yankees Manager Aaron Boone said he expected him to be all right but pulled him as a precaution. Torres leads the Yankees, the American League East champions, with 38 home runs and is hitting .284 with 90 R.B.I.

Aaron Judge and Tyler Wade homered for the Yankees a day after they clinched the division. They are still competing for the best record in the majors and home-field advantage throughout the postseason — the Yankees and Houston each began the day with 100 wins.

Justin Smoak hit a go-ahead, two-run homer in the seventh to help Toronto match a season high with its fifth straight victory. He connected off Tommy Kahnle (3-2) as the Yankees’ bullpen wobbled in the late innings for the third time in a week.