DENVER (AP) — Colorado Rockies right-hander Antonio Senzatela will miss the rest of the season with a torn ACL in his left knee.

Senzatela was hurt during his start Thursday at St. Louis. He and first baseman Elehuris Montero were both racing toward Brendan Donovan’s second-inning grounder when Senzatela broke toward first base in a sudden change of direction.

His knee buckled and he fell to the ground, holding his leg in his hands and clearly in pain. Manager Bud Black says Senzatela will have surgery and hopefully be ready to return in six to eight months.