Giants manager Bob Melvin said Wednesday that Harrison (shoulder) is unlikely to be activated from the 15-day injured list before the season ends Sept. 29, MLB.com reports.

The Giants placed Harrison on the 15-day injured list, retroactive to Wednesday, due to left shoulder inflammation.

Harrison (7-7) took the loss Tuesday against the Diamondbacks, allowing six runs on seven hits and a walk while striking out three over 2.2 innings.

Harrison did not factor into the decision in Tuesday's loss to Atlanta, allowing three runs on six hits and two walks while striking out six over five innings.

Harrison (5-4) earned the win over the Twins on Friday, allowing one run on five hits and a walk while striking out three over 5.1 innings.

Harrison (ankle) was reinstated from the 15-day injured list ahead of his start Saturday against the Guardians, Alex Pavlovic of NBC Sports Bay Area reports.

Harrison (ankle) will be reinstated from the 15-day injured list Saturday to make a start in Cleveland.

Harrison (ankle) will throw one more bullpen session then rejoin the rotation during the Giants' six-game road trip that begins Thursday, Alex Pavlovic of NBC Sports Bay Area reports.

Harrison (ankle) will throw a bullpen session Friday, Shayna Rubin of the San Francisco Chronicle reports.

The Giants placed Harrison on the 15-day injured list Sunday with a right ankle sprain.