The Golden Eagles, who won their second in a row, will play New Mexico State in the semifinals Friday. UC Irvine will face Central Michigan in the consolation round.
Southern Miss outrebounded UC Irvine 46-39.
The Golden Eagles sprinted ahead 12-3 and never trailed.
Starring and Pelham staged a first-half shootout, each scoring 12 points, as Southern Miss grabbed a 30-24 edge at the break.