The two combined for a season-high 14 strikeouts, including 10 by Gray and four by John in the final two innings.
"Yeah, I felt like everything was working for me," Gray said. "I threw everything for strike."
But it didn't come without suspense in the late innings.
Oregon had runners on second and third in the bottom of the eighth and first and third in the bottom of the ninth with a chance to tie it, but could not plate a run in either of those situations.
The Ducks tied it when second baseman Aaron Payne blasted a double down the right field line and scored shortstop J.J. Altobelli.
Toal made it 2-1 in the top of the seventh as Toal recorded his second RBI of the evening on a single knocking home right fielder Cody Reine.
Oregon cut the lead to 3-2 when center fielder Brett Thomas crossed the plate on an RBI single by Altobelli, but that's all the damage the Ducks could do.
Overton polished off a complete game shutout with six strikeouts and no walks on 98 pitches, not surpassing 10 pitches in any of the final seven innings.
"It was outstanding and that's what we told him," said head coach Sunny Golloway. "I thought he minimized his pitch count. We told him he had to force contact to get us through it quickly and let the defense do the work. It was really big with the double dip today and another game tomorrow."
He started off with his only trouble of the day, allowing two runs in the top of the second, but rolled from there.
The Sooners tied it up when catcher Hunter Lockwood hit a sacrifice fly and Bushyhead scored on a double steal.
After 11 scoreless half-innings, the Sooners finally broke the 2-2 tie when second baseman Jack Mayfield came up with a huge RBI double.
"He had a game-winning hit earlier in the year, you know, he's pretty much ‘Mr. Clutch' late in games," Golloway said. "He has a lot of confidence and a lot of calmness about him."
White and third baseman Garrett Carey each added RBIs later in the inning to extend OU's lead and help them win the day game.
"West Virginia played really well," Golloway said. "Their pitcher was outstanding."
OU now heads to Corvallis, Ore., to finish up the Nike Showcase in a road contest at Oregon State at 1 p.m. CT/11 a.m. PT.