The victory, ETBU's third in a row, lifts the Tigers to 6-8 overall and 6-6 in the American Southwest Conference East Division. Austin College drops to 4-11 and 3-9.
AC's Chris Caudle was fouled with just over two seconds remaining in regulation with the Kangaroos trailing by two, 53-51. Caudle made the first free throw but the second rimmed out, allowing Mumphrey to grab the rebound. The ETBU freshman forward then hit the first free throw to make it 54-52, but the second was missed. The 'Roos, however, could not get off a shot when the buzzer sounded.
The game was a tight defensive battle throughout, with the first half highlighted by quick scoring runs by both teams. Austin College started the game on fire, jumping out to a 10-0 lead by making their first four shots, two of which were three-pointers. The 'Roos bumped the score up to 13-2 nearing the 15-minute mark before ETBU got rolling.
The Tigers peeled off 17 unanswered points to take a 19-13 lead, but AC rallied to score the next 11 points to take a 24-19 lead. The 'Roos held the lead until the break and took a 27-24 lead into the locker room.
ETBU rallied in the second half and took an eight-point lead, 53-45, late in the second half. But the 'Roos battled back to set the stage for the dramatics at the end of the game.
ETBU was led by junior guard Cedric Isom's 20 points, six rebounds and five assists. Isom also had five steals and two blocks on the night.
Chris Isom added 15 points and four boards, but no other Tiger scored more than Allen Colbert's seven.
AC was led by Caudle's 10 points and seven rebounds, as the 'Roos pounded the Tigers in the rebounding department with a 49-31 advantage.
The Tigers were 1-of-7 at the free throw line, with the one made charity shot coming on Mumphrey's last-second free throw.
ETBU hosts University of the Ozarks in a battle for second place in the ASC East Saturday at 3 p.m. in Ornelas Gym.