FAYETTEVILLE, Ark. -- Brandon Allen threw a 25-yard touchdown pass to Drew Morgan on the first play of the fourth overtime, also converting on the 2-point conversion, to lead Arkansas to a 54-46 win over Auburn on Saturday.
The win is the first for the Razorbacks (3-4, 2-2 Southeastern Conference) over former offensive coordinator and current Tigers coach Gus Malzahn in three games, and it keeps Arkansas' bowl hopes alive.
Alex Collins rushed for 105 yards and a touchdown on 25 carries to lead Arkansas, topping 100 yards rushing for the fourth time in five games.
Sean White was 19-of-32 passing for 254 yards for Auburn (4-3, 1-3), which had its two-game winning streak snapped.
The game is the longest in major college football this season, according to STATS.
After the two teams traded touchdowns in the first three overtimes, also both converting their 2-point conversions in the third, Arkansas quickly went up 54-46 to open the fourth extra period.
Allen hit Morgan in the right flat, and the receiver sprinted down the sideline -- diving into the end zone for the touchdown. Allen, who was 19-of-31 passing for 233 yards and three touchdowns, then connected with Kody Walker for the 2-point conversion.
The Tigers had a final chance to try and tie the game in the fourth overtime, but Ricardo Louis dropped a pass in the end zone on second down, and White's fourth-down attempt to Louis was broken up by Arkansas safety Josh Liddell.
Razorbacks coach Bret Bielema entered the game 0-2 against Auburn under Malzahn, an Arkansas native who made a name for himself while coaching high school football in the state and was the Arkansas offensive coordinator for one season.
Arkansas took a 24-21 lead with 1:07 remaining in regulation when freshman Cole Hedlund made a 25-yard field goal, capping a 13-play, 67-yard drive that appeared to by the game winner.
However, Auburn drove 50 yards in eight plays after that -- highlighted by a pair of long passes by White to Louis -- and tied the game at 24-24 with 4 seconds remaining on a 41-yard field goal by Daniel Carlson.
Peyton Barber then ran the ball on each of the Tigers three plays to open overtime, easily putting Auburn up 31-24 with his 2-yard plunge. Barber finished with 120 yards rushing and four touchdowns on 37 carries.
Arkansas led 14-0 in the first half before Auburn tied the game at 14 with an 8-yard touchdown run by Jason Smith on the opening drive of the second half.
After the Razorbacks went back up 21-14 on a 7-yard run by Collins, the Tigers once again tied the game after backup quarterback Jeremy Johnson ran in from a yard out midway through the fourth quarter.
Hedlund, however, capped Arkansas' 13-play, 67-yard drive with his 25-yard field goal to put the Razorbacks up 24-21 with 1:07 remaining -- improving the freshman to 6 of 9 on field goals for the season.
Arkansas appeared to have the game under control for much of first half, holding the Tigers to 14 yards of offense on their first 14 plays -- aided by six dropped passes by Auburn wide receivers.
However, after taking a 14-0 lead after Allen's 23-yard touchdown pass to Jeremy Sprinkle, the Razorbacks failed to take advantage of a 26-yard Auburn punt that gave them the ball at the Tigers 38 late in the half.
The drive ended for Arkansas after Allen was intercepted by Kris Frost at the Auburn 4-yard line, after which the Tigers put together their best offensive possession of a day -- a 16-play, 96-yard drive that was capped by Peyton Barber's 1-yard touchdown run with 30 seconds left before halftime.