The six-foot-four 240-pounder was among the collection of prospects the Phillies obtained last summer in the trade that sent Cole Hamels and Jake Diekman to Texas.
After joining the Phillies, Eickhoff quickly made his major league debut, posting a 3-3 record with a 2.65 ERA and a .245 batting average against in eight starts.
The ailment is not expected to keep Eickhoff out of action for very long. The Phils anticipate the he’ll still be ready to start the regular season with the big club.
Eickhoff was originally a 15th round draft choice of the Rangers in 2011.