The Pittsburgh Pirates activated outfielder Andrew McCutchen from the 10-day injured list on Friday.

McCutchen had been sidelined due to left knee inflammation.

Also Friday, the Pirates placed pitcher Ben Heller on the 15-day injured list with right shoulder inflammation and announced fellow right-hander Daulton Jefferies will begin a rehab assignment Friday with Triple-A Indianapolis. Jefferies, 29, currently is on the 60-day injured list with right elbow discomfort.

McCutchen was injured while running the bases following a single in the seventh inning of the Pirates' 5-3 victory over the Seattle Mariners on Aug. 16. The victory snapped a 10-game losing skid for Pittsburgh.

McCutchen, 37, is riding a season-high 12-game on-base streak. He is batting .235 with 16 homers and 40 RBIs in 101 games this season.

A five-time All-Star and 2013 National League MVP, McCutchen has a career .274 average with 315 homers and 1,085 RBIs in 2,108 career games with the Pirates, San Francisco Giants, New York Yankees, Philadelphia Phillies and Milwaukee Brewers.

Heller, 33, is 0-1 with an 11.25 ERA in eight relief appearances this season with Pittsburgh.

He is 2-1 with a 4.65 ERA in 58 relief appearances with the Yankees, Atlanta Braves and Pirates.