Wilkerson had 22 points and 10 rebounds and Whiteside 17 points and 10 rebounds for the Thundering Herd (23-8, 11-5 Conference USA), who, with Tulsa's loss to Memphis on Saturday, clinched the No. 4 seed in the conference tournament and received a bye to the quarterfinals on Thursday. Marshall will play the winner of Wednesday's Rice-Tulsa contest.
Papa Dia had 18 points and 13 rebounds for SMU (14-16, 7-9), who earned the No. 8 seed in the tournament and will play ninth-seeded UCF on Wednesday. Mouhammad Faye, with 10 points, was the only other Mustang to score in double figures.
Dago Pena had 10 points for Marshall.