PITTSBURGH — Pirates right-hander A.J. Burnett is hopeful of returning to the rotation by mid-September following a 71-pitch bullpen session on Sunday.

The 38-year-old Burnett has been on the disabled list since July 31 with a strained flexor tendon in his right elbow.

“It was good, better than expected,” Burnett said of the bullpen session. “The pain is gone and I feel good.”

Burnett is scheduled to throw a simulated game Friday and then hopes to make a start during a four-game home series against the Chicago Cubs from Sept. 15-17.

Burnett is 8-5 with a 3.06 ERA in 21 starts. But he is 1-2 with a 10.13 ERA in three starts since the All-Star break.

The Pirates also shuffled their rotation Sunday, announcing that Gerrit Cole will start Tuesday night at Milwaukee instead of Wednesday night. Left-hander Jeff Locke will pitch Wednesday instead of Tuesday.

The move put Cole in line to pitch next Sunday night against the Cardinals in the finale of a pivotal three-game series at the NL Central leaders.