WASHINGTON -- C.J. Anderson scored 21 points and Massachusetts held off La Salle 69-67 on Wednesday night in the first round of the Atlantic 10 Conference Tournament.

No. 13 seed UMass (13-19) will face fifth-seeded George Mason (15-16) in a Thursday quarterfinal.

Pookie Powell's 3-point play gave La Salle its last lead, 62-61, before UMass pushed ahead to 68-67 with 44 seconds to play. La Salle's B.J. Johnson blocked Unique McLean's jumper with 14 seconds remaining, but Powell missed a jumper and a 3-pointer in the final eight seconds.

Luwane Pipkins added 15 points, Malik Hines had 14 and Carl Pierre 11 for the Minutemen. Anderson and Pipkens both shot 4 of 7 from long range.

Tony Washington scored 20 points to lead No. 12 seed La Salle (13-19). Johnson and Powell chipped in 18 points apiece.