The Arizona Diamondbacks placed ace right-hander Zac Gallen on the 15-day injured list Friday due to a right hamstring strain.

Arizona recalled right-hander Slade Cecconi from Triple-A Reno in a corresponding move, keeping its 40-man roster at 39 members.

Gallen lasted just six pitches in his Thursday night start against the New York Mets. He said after the game that he hurt the hamstring while allowing a leadoff single to Francisco Lindor; it didn't become clear that Gallen was hurt until his first offering to the next batter, DJ Stewart.

"It's not great news, I'm not going to lie," manager Torey Lovullo said after the game, "and we will eventually find out what the solutions are."

Gallen already left a start and missed a turn in the rotation earlier this season due to right hamstring tightness.

Gallen, 28, is 5-4 with a 3.12 ERA in 11 starts this season. He was coming off a career year in 2023, when he finished third in National League Cy Young Award voting after posting a 17-9 record, a 3.47 ERA and 220 strikeouts in 210 innings across 34 starts.

Cecconi, 24, made his major league debut last year and appeared in six games (five starts) for Arizona earlier this season. He went 1-4 with a 6.12 ERA in those games.