Burnett was scheduled to start Friday, but he told Pirates skipper Clint Hurdle Wednesday of his calf issue.
Burnett has pitched well this season compiling a 3.12 ERA, 1.13 WHIP and is third in the National League with 99 strikeouts.
The DL move is retroactive to Sunday so Burnett is eligible to return June 23.
Pitcher Charlie Morton takes Burnett’s roster spot.
The Pirates also released reliever Jose Contreras, who was on the 15-day DL with back pain.
Copyright 2013 ABC News Radio
Eliott C. McLaughlin, CNN Newswire