Kimbrel has missed the past couple of weeks with inflammation in his right knee.
The Cubs have struggled all season to hold leads, blowing 10 saves since the All-Star break, the most in the National League.
On Friday, setup man Brandon Kintzler was activated from the IL, after rehabbing a pectoral injury, and he promptly blew a save after walking in the tying run against the Pittsburgh Pirates. The Cubs and Pirates play the rubber game of their series in Williamsport on Sunday night. A victory would give the Cubs their first road series win since mid-May.
Kimbrel has nine saves but a 5.68 ERA in 14 games with the Cubs since signing a three-year, $43 million deal with them in June.
Reliever Steve Cishek (hip) is due to come off the injured list later this week. The Cubs also called up outfielder Mark Zagunis to serve as their 26th man for Sunday night's game.
The Cubs sent right-hander Duane Underwood to the minors in the corresponding move when Kimbrel was activated.