The senior, who snagged an interception in the first half, was in perfect position for another early the fourth quarter. But Auburn quarterback Brandon Cox's underthrown pass sailed through Vaughn's hands, into tight end Cooper Wallace's in the back of the end zone and turned into the Tigers' game-clinching touchdown.
Likewise, Arkansas' hopes of a big win against No. 21 Auburn slipped through its grasp in the second half of its loss in front of 71,673 in Reynolds Razorback Stadium on Saturday night. The Hogs grabbed a 10-6 halftime lead behind a sweltering defense, but Cox threw three second-half touchdown passes, tailback Kenny Irons rushed for a game-high 182 yards and the Tigers held Arkansas to two touchdowns en route to their fifth straight win.
"We have to learn how to play a complete game," Vaughn said. "We played a great first half, but did not finish. We have to learn to finish the football game."
Arkansas was outscored 28-7 in the second half, outgained 158-25 in the decisive third quarter and lost its ninth straight against a ranked opponent.
The Razorbacks are 11-19 against ranked teams under Coach Houston Nutt, with their last win coming in the 38-28 win against Texas in Sept., 2003.
But Arkansas thought it had a good chance against the Tigers after leaning on its defense early on. Reggie Herring's unit pressured, harassed and hit Cox throughout the first half. The sophomore, who made his first road start, was sacked two times, hurried several others and threw two interceptions before the break.
Cox hadn't thrown an interception since the Tigers' season-opening, 23-14 loss against Georgia Tech. He threw four costly interceptions in the second half against the Yellow Jackets and Arkansas scored 10 points off his two mistakes Saturday.
"They came out and had a great game plan and were blitzing about every play," Cox said. "It took us by surprise."
The Hogs couldn't get into the end zone after the first mistake, settling for kicker Chris Balseiro's 19-yard field goal and a 3-0 lead with a 19-yard field goal. Arkansas got into the end zone late in the second quarter when tailback Darren McFadden scored on a 5-yard touchdown run to make it 10-3.
Auburn notched two John Vaughn field goals in the first half — the last coming with 34 seconds remaining in the second quarter — but Arkansas confidently strolled to the locker room with a 10-6 lead.
"We felt great," Nutt said Arkansas' first-half performance. "We felt like we played a great half of football against the defending (SEC) champions."
But the good feelings didn't last long.
Auburn adjusted to the Razorbacks pressure, kept the ball on the ground and didn't have any trouble moving the ball after the break, scoring touchdowns on four straight possessions. Arkansas — which reached Auburn territory on five first-half possessions, but scored only twice — had trouble finding room against the Tigers and struggled once again against one of the SEC's top defenses.
"We took their best shot," said Auburn coach Tommy Tuberville. "We got frustrated at first but we kept our confidence throughout the game, especially in the second half when we just dominated with our offensive line."
Cox led the Tigers on a 7-play, 73-yard drive that ended with his 17-yard touchdown pass to receiver Devin Aromashodu. The Tigers added to it a little later, eating 7:01 off the clock on a 14-play, 85-yard drive that resulted in Cox's 5-yard touchdown pass to tailback Tre Smith. Auburn held a 20-10 lead after the scores.
"It's real simple," Herring said. "Their running game was the difference in the second half. They put it to us in the second half and we didn't respond. It's as simple as that. They dominated the line of scrimmage; they just outphysicaled us and they took it to us in the second half and that was the difference in the game."
Arkansas quarterback Robert Johnson helped the Tigers add to it on the next possession. The sophomore, rolling to his left to avoid pressure, whipped a pass downfield that was intercepted by Auburn linebacker Karibi Dede at the Arkansas 24.
Wallace scored five plays later, snagging the ball that slipped through Vaughn's hands to help the Tigers grab a commanding 27-10 lead. Cox finished completing 17 of 26 passes for 203 yards with 3 touchdowns and 2 interceptions.
Auburn outgained Arkansas 436 to 322.
Johnson, completed 17 of 28 passes for 174 yards with the interception, but also hurt the Razorbacks by losing a fumble in the first half. Arkansas reached Auburn's 11 when he began to throw a pass and tried to pull it back. The ball hit the turf and was scooped up by Dede to kill a scoring opportunity.
"I went to throw the ball and they gave me a funny look and I went to hold onto it and it just slipped out of my hands," Johnson said. "I've got to do better on my part on something like that.
"When we're in the red zone like that we have to score. It's a must that we score.
It was one of several missed opportunities for Arkansas, which reached Auburn territory on five of its first half possessions. The Razorbacks had to settle for a field goal in the first quarter after reaching Auburn's 2, had a field goal blocked in the second quarter and failed to score points when Johnson fumbled.
McFadden was the only bright spot for Arkansas' offense, rushing for 108 yards and 2 touchdowns. His second touchdown cut Auburn's lead to 27-17 in the fourth quarter, but Smith added a 7-yard touchdown run for the Tigers late in the game.
Tigers Run Over Razorbacks
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