St. Louis Cardinals manager Mike Shildt said Monday that starting pitcher Carlos Martinez recently underwent surgery to repair a torn ligament in his right thumb, according to Zachary Silver of MLB.com.

While Martinez is without an official timeline, he is at risk of missing the remainder of the 2021 season while recovering from surgery, Silver notes.

Martinez injured his thumb while fouling off a ball during an at-bat against the Colorado Rockies on July 4.

The 29-year-old has had a trying time on the mound this year, going 4-9 with a 6.23 ERA, a 1.37 WHIP, and 57 strikeouts over 82 1/3 innings.

This could spell the end of his Cardinals tenure as he's eligible to hit free agency if the club doesn't exercise his $17-million option for 2022.

A two-time All-Star (2015, 2017), Martinez has a 62-52 career record with a 3.74 ERA and 1.30 WHIP over 967 innings across nine seasons in St. Louis. While he's primarily served as a starter, Martinez has occasionally worked out of the bullpen and was the team's closer in 2019 when he recorded 24 saves.

The Cardinals' rotation has been crushed with injuries all season. Ace Jack Flaherty hasn't pitched since May 31 thanks to a strained oblique, while Miles Mikolas has been limited to four innings with forearm tightness. Kwang Hyun Kim missed the start of the campaign with a back injury but is healthy now.