Houston, TX (SportsNetwork.com) - Houston Astros outfielder George Springer has been reinstated from the 7-day concussion disabled list and will start Wednesday's game against the San Francisco Giants.

Springer, who has missed Houston's last six games, will bat fourth and play right field in Wednesday's tilt, in which Brett Oberholtzer will make his season debut for the Astros.

Oberholtzer, sidelined since spring training with a blister on his left index finger, was activated from the 15-day DL prior to Wednesday's contest.

Springer suffered his injury when he went head-first into the right-field wall while making a running catch in Houston's 7-1 loss to Texas on May 5. The 25- year-old was hitting just .192 with four homers and 12 RBI, striking out 35 times in 99 at-bats, prior to the concussion.

Oberholtzer tuned up for Wednesday's outing with a pair of rehab starts for Triple-A Fresno, the last of which he struck out nine over 5 1/3 scoreless innings.

The left-hander compiled a 5-13 record with a 4.39 ERA in 24 starts for the Astros last season.

To make room on the active roster, Houston optioned reliever Kevin Chapman and outfielder Robbie Grossman to Fresno.

Grossman was hitting a lowly .143 (7-for-49) in 24 games this season.