The Tigers (18-16) awakened from a poor 20 minutes and a 36-30 deficit to shoot 24 of 61 (39.3%) overall and make 16 of their season-high 44 attempts (36.4%) from long range.
Auburn’s Kaden Magwood, who last played on Jan. 6, notched a career-high 14 points. Tahaad Pettiford had 11 points, five rebounds and four assists. Elyjah Freeman totaled four points, 10 rebounds and four assists.
The Tigers will host Seattle University in the second round on Saturday.
Sun Belt Player of the Year Chaze Harris notched 29 points, eight boards and six assists for South Alabama (21-12). Stephen Williams had 14 points and nine rebounds, and Jayden Cooper put in 14 points.
The visiting Jaguars showed they were ready to play from the start as Cooper drilled a pair of long shots for a 6-2 lead at 17:27, but Hall put Auburn up for the first time with a deep trey for an 11-10 lead.
Just over 11 minutes into the matchup, Harris and Hall had each scored in double figures, combining for eight field goals.
Shortly before five minutes left in the first half, Harris and Hantz Louis-Jeune made buckets to give the Jaguars a 30-22 edge, and the lead grew to 36-25 at 2:36 as they converted 10 consecutive shots to lead 36-30 at the break.
Harris had 18 points as the Sun Belt school made 14 of 28 (50%) from the floor.
Hall tallied 16 for the Tigers, but the Southeastern Conference team hit just 9 of 36 (25%) of its shots.
Auburn swung the momentum by soaring off on a 13-2 run to start the second half in almost five minutes played. Magwood and Overton netted 3-balls for a 52-44 advantage with nearly 11 minutes left.
Magwood added to his career outing by draining a trey, and Overton followed that with another from out deep as the Tigers took full control with 7:28 to go, leading 61-48.
