Avery Woodson hit a 3-pointer with 3:45 left to give Memphis a 59-53 lead, but the Tigers did not score again in regulation, missing three shots from beyond the arc and a field goal attempt by Kedren Johnson with :19 left. Meanwhile, UCF rallied. Staphon Blair got to the basket for a pair of layups and Brandon Goodwin added a third with :04 left to force overtime.
Memphis reversed the script in overtime, holding UCF scoreless for almost the first 2:50 of the extra period.
In his second game back, Nichols finished with 20 points to lead the Tigers (17-10, 9-5 American), who now have won three straight.
Goodwin led the Knights (12-14, 5-10) with 15 points, with Blair adding 12 more.