Gophers' starter Joshua Culliver gave up a 3-run home run in the top of the fifth inning to give Oklahoma a 3-2 lead, its first of the game.
Minnesota's offense wasn't able to respond after the blast. The Sooners (27-14) built on their lead and took the series in a 5-2 victory at Siebert Field on Sunday.
"In order to score some runs and have a good offense, you've got to be able to put together four or five or six good at-bats in a row, and that's been our problem," Gophers head coach John Anderson said.
The Gophers (17-20, 7-5 Big Ten) started the scoring off in the bottom of the first inning when outfielder Ben Mezzenga hit a double. On the next at-bat, shortstop Jordan Kozicky hit him in with a double off the left field fence. Kozicky went 1-for-2 with two walks before he exited the game in the ninth inning with a slight foot injury, though he said he'd be back next game.
"I just got a fastball that was up, and I saw it really well," Kozicky said. "As an offense, we hit really well for the first five innings."
Minnesota added to its lead in the second inning when outfielder Riley Smith grounded out to the shortstop and third baseman Jack Wassel scored from third. That would be all the Gophers would muster on the scoreboard.
The 3-run home run from Sooners' outfielder Brady Harlan gave his team all it needed for a victory.
"[Culliver] made the pitch that he wanted to," said junior pitcher Brett Schulze who finished the final two innings and allowed one run. "I know he's OK with it and wants that one back, but he still gave the team a chance to win."
Culliver took the loss, pitching seven strikeouts and no walks while allowing eight hits in 5 2/3 innings of work.
Oklahoma catcher Brady Lindsly hit an RBI double in the sixth inning and batted in another runner in the eighth inning, for a 5-2 score.
"I think it's good for us to push the pause button here and try to reset, and talk through some of these things," Anderson said, after the Gophers lost the second-straight series at home. "I don't think we need to play more, to be honest with you, right now. I think we need to sit down and evaluate where we're at."
The Gophers won the first game of the series 8-1 on Friday. Gophers' catcher Eli Wilson hit 3-for-4 with two RBIs, and Wassel hit a three-run home run. Gophers' right-handed sophomore Sam Thoresen threw five innings and allowed no runs to collect the win.
On Saturday, Minnesota dropped the second game of the series 2-1 at Target Field. Oklahoma led 2-0 going into the bottom of the fifth inning and then Minnesota outfielder Easton Bertrand hit a solo home run to left field. The Gophers couldn't get the tying run, and they lost in the major league stadium.
Minnesota will play Indiana in a three-game series in Bloomington, Indiana this weekend. The Hoosiers lead the Big Ten with an 8-3 conference record.