DENVER -- Milwaukee Brewers outfielder Ryan Braun left Friday night's game at the Colorado Rockies with a left calf sprain. He is expected to undergo an MRI to determine the severity.

Braun singled and drove in a run in the top of the first inning and then played the field in the bottom half. He said after the game he felt the injury as he was running to first base.

Braun left after Milwaukee batted in the second inning and was replaced by Ben Gamel.

"I feel a bit better now than when it first happened, so I'm encouraged by that," Braun told reporters after the game. "Just trying to stay optimistic and gather more information and see where we're at."

The 35-year-old Braun has been in and out of the lineup all season because of back issues. He is hitting .285 with 22 home runs and 75 RBIs.

The Brewers already have locked up a playoff berth but are still in a race with the Nationals to see who will host the National League wild-card game.

"The timing [of the injury] is not ideal, but it's a part of baseball," Braun said.

Milwaukee is also dealing with a hobbled Mike Moustakas, who has missed time dealing with a bruised hand and was out of the lineup on Friday with a sore right elbow.

The Associated Press contributed to this report.