NEW YORK -- Terry Nolan Jr. scored 20 points, including six in overtime, to lead George Washington to a 68-64 win over UMass in the opening game of the Atlantic 10 tournament on Wednesday.

Maceo Jack added 19 for the No. 12 seed Colonials (9-23), which will play fifth-seeded George Mason in the second round Thursday. The Patriots swept the regular-season series against George Washington.

Keon Clergeot scored 25 points, Carl Pierre had 12 and Rashaan Holloway finished with 11 for No. 13 seed UMass (11-21).

Unlike the only regular season meeting -- which the Colonials won 79-67 -- what transpired Wednesday at the Barclays Center was taut throughout. Nolan opened the overtime with a 3 and George Washington a five-point lead with three minutes left after Justin Mazzulla made two free throws.

Massachusetts drew even at 63-all with 39 seconds to play after a Clergeot layup and a Sy Chatman putback on consecutive possessions.

Nolan's layup 12 seconds later gave the Colonials the lead for good. On the ensuing possession, Pierre made 1 of 2 free throws but Mazzulla knocked down two foul shots, and Nolan added another to seal the win.