George Mason (11-14, 5-7 Atlantic 10 Conference) has won two of its last three games. George Washington (10-15, 3-9) has lost five of its last six, and is now 0-8 on the road.
Livingston was 4 of 7 from the floor and matched a career-high with nine assists. Grayer, who had three straight double-doubles before a foot sprain limited his play in George Mason's last three games, collected his sixth double-double. Justin Kier added 13 points and AJ Wilson had 11 for the Patriots.
The Patriots had a 14-point lead with 3:16 to play. Watanabe scored nine points during a 17-7 surge that pulled the Colonials to 68-64 with 18 seconds remaining. Livingston shot 4 of 4 from the line to seal it.
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