Thomas scored 15 points with eight rebounds, seven assists and five steals in the victory - UMass-Lowell's seventh decided by 10 points or fewer and its sixth second-half comeback. Chad Holley scored 14 and Tyler Livingston 13 for the River Hawks (9-8, 3-1 America East).
Thomas and Lance Crawford wrapped back-to-back baskets around a Maine miss to give UMass-Lowell a 52-51 lead with just under eight minutes to play. Maine threatened several times but did not regain the lead.
Beal missed both ends of a two-shot foul with Maine trailing 60-59 with 12 seconds to play.