Barnes (shoulder) was activated from the 60-day injured list Thursday, Chris Cotillo of The Springfield Republican reports.
Barnes has been sidelined by the shoulder issue since late May and has been cleared to rejoin the big-league roster after an eight-game rehab assignment in the minors. The veteran right-hander surrendered seven earned runs across 7.2 innings with Triple-A Worcester and Double-A Portland. Barnes had a 7.94 ERA, 1.71 WHIP and 14:12 K:BB across 17 frames prior to the injury and will likely fill a low-leverage role now that he's healthy.