Turnbull, 31, has posted a 3-0 record with a 2.65 ERA (16 ER, 54.1 IP) and 58 strikeouts against 20 walks over 17 games (7 starts) for the Phillies this season.
The injury could sideline him until mid-August.
In seven starts, Turnbull is 2-0 with a 1.78 ERA (7 ER, 35.1 IP) and has held the 137 batters he has faced to a .146/.234/.276 slash line (.510 OPS).
He started the season in the starting rotation before moving to the bullpen when Taijuan Walker returned to the starting rotation.
Ironically, Turnbull was likely to again slide into the starting rotation as Walker is dealing with a blister on this throwing hand.
“It’s probably gonna be six weeks, could be eight weeks," manager Rob Thomson said. "With his injury history, we’re gonna be careful with him and make sure we do this thing right.”
It's unclear as of now what the Phillies intend to do regarding the starting rotation.
Marte, 29, was on the 15-day injured list from May 3 to June 24 with right shoulder inflammation; he was reinstated on Tuesday and optioned to Lehigh Valley. He appeared in 10 games for the IronPigs on his rehab assignment.
In 12 games for the Phillies this year, Marte has a 2.70 ERA (4 ER, 13.1 IP) with 12 strikeouts.
