David Godbold scored 25 points and OU held off a second-half surge by St. Joseph's to claim a 72-64 win at the BJCC in Birmingham, Ala.
The Sooners (23-11) will play third-seeded Louisville at 4 p.m. Sunday at the BJCC.
Godbold knocked down three treys and scored Oklahoma's first 11 points of the second half as they built a 19-point lead.
It was all part of a 25-6 run that began in the first half when the game.
Not only that, but Godbold defended Pat Calathes, the Hawks' leading scorer. Calathes, who averaged over 18 a game, was held to no points and just two field-goal attempts in the first half. He finished with just six points.
Still, St. Joe's was able to fight back and used a 10-0 run to pull within four points. In fact, the Hawks twice pulled within that margin, the last being on a Garrett Williamson putback with 3:31 to play.
But Blake Griffin answered with a pair of field goals and St. Joe's was held without a field goal the rest of the game.
Rob Ferguson led the Hawks with 21 points.
Oklahoma shot 57 percent from the field (24-of-42) and was 6-of-14 from 3-point range. Godbold made five of those.
Longar Longar poured in 14 points. Blake Griffin scored 12 on 6-of-7 shooting. Griffin also had four assists as he and Longar were double-teamed nearly every time they touched the ball in the post.
Austin Johnson added 10 points and five assists for the Sooners.