Oklahoma State evened the series at 1-1 and improved to 30-17 overall and 10-10 in league play, while Texas A&M fell to 27-20-1 and 7-13 in conference action.
Catcher Jeff Parrish opened a four-run fourth inning with a solo homer to left, his 12th of the year. Ty Wright would later add a RBI single and Corey Brown then roped his second homer of the weekend and 11th of the season to push the lead to 6-0.
Chris Gutierrez added a RBI infield bunt single in the eighth that scored Keanon Simon who reached on a triple down the right field line. Adam Carr hit a triple, his fifth of the year, in the ninth and scored on a passed ball to make the score 8-0.
Simon tied a career high with three hits on the night to lead Oklahoma State, while Corey Brown, Mike Hernandez and Chris Gutierrez each had two hits in the winning effort.
Aggie starter Austin Creps (2-1) was charged with the loss after giving up three runs on five hits in three innings of work.
The teams will close out the series Sunday afternoon at 2 p.m.