Astros outfielder Jason Bourgeois was 2-for-4 with a walk and two runs scored in his first rehabilitation game (left oblique).
RedHawks starter Gustavo Chacin (2-2) dealt five scoreless frames with three hits, two walks and two strikeouts in the winning decision. Express starter Derek Hankins (5-3) allowed seven runs and eight hits in three innings for the loss.
Oklahoma City opened the scoring in the first inning, sending all nine batters to the plate in a five-run frame. Bourgeois led off the game with a triple and scored on an Anderson Hernandez single for a 1-0 score. Hernandez scored later on a Brian Dopirak single for a 2-0 score. Koby Clemens later scored on a Hankins wild pitch for a 3-0 lead. J.B. Shuck capped off the inning with a two-run single, opening a 5-0 advantage.
The RedHawks added two more in the third inning. Brandon Barnes walked and scored on a Tommy Manzella triple for a 6-0 lead. Manzella later scored on a Shuck RBI single for a 7-0 score.
In the fourth inning, Koby Clemens belted a two-out, solo home run to left field, his second in as many games, extending the lead to 8-0.
Round Rock added a run in the seventh inning. Brad Nelson doubled, moved to third on a groundout and scored on a groundout by Omar Quintanilla for an 8-1 score.
The RedHawks countered with a run in the bottom of the seventh inning when Dopirak singled, moved to third on a single by Manzella and scored on a Shuck single for a 9-1 game.
Oklahoma City capped off the night in the eighth inning when Barnes singled in two runs on a two-out single for an 11-1 score.
RedHawks RH Nelson Figueroa will face Express RH Brett Tomko in the series finale Friday at 7:05 p.m. Tickets are available through the RedHawks box office at 405-218-1000 or by visiting okcredhawks.com.