Oklahoma State scored eight runs in the first two innings, and seven runs in their last at-bat to beat Oklahoma 19-to-8 in a Bedlam baseball game in Stillwater on Tuesday night.
The Cowboys gave up three runs in the first inning on a three-run home run by Dakota Harris, then responded with a five-run bottom of the first.
OSU added three more runs in the second inning and never trailed again.
OU used eight pitchers in the game and they walked 13 Cowboys.
OSU used six pitchers and walked 8 Sooners.
Oklahoma threatened in the top of the eighth, loading the bases with two outs and trailing 12-8.
Isaac Stebens struck out Jackson Nicklaus to end the inning, and then OSU got seven runs in the top of the 8th.
David Mendham led OSU at the plate, going 3-for-5 with five runs batted in, while both Roc Riggio and Chase Adkison drove in three runs apiece.
OSU has won six of the last eight meetings against OU and eight of the last 10 in Stillwater.
OSU improved to 25-13 on the season, while OU dropped to 19-19.
The game was a non-conference game that will not count in the Big 12 standings.
The Cowboys visit Kansas in a three-game series starting Friday, while the Sooners are at Texas in a three-game series starting Friday.