How Auburn defeated Louisville

090515 ATLANTA: Auburn wide receiver Ricardo Louis gets in the endzone past Louisville safety Josh Harvey-Clemons for a 31-10 Auburn lead during the fourth quarter in the Chick-fil-A Kickoff Game on Saturday, Sept. 5, 2015, in Atlanta. Curtis Compton / ccompton@ajc.com

Credit: ccompton@ajc.com

Credit: ccompton@ajc.com

090515 ATLANTA: Auburn wide receiver Ricardo Louis gets in the endzone past Louisville safety Josh Harvey-Clemons for a 31-10 Auburn lead during the fourth quarter in the Chick-fil-A Kickoff Game on Saturday, Sept. 5, 2015, in Atlanta. Curtis Compton / ccompton@ajc.com

Auburn defeated Louisville 31-24 in the Chick-fil-A Kickoff game at the Georgia Dome on Saturday.

It wasn’t pretty, but the No. 6 Tigers emerged behind a defense that held the Cardinals in check until near the end of the third quarter.

Here are five moments that determined the outcome:

Cardinals’ early miscue

Bobby Petrino tried to flex his schematic muscle on the game’s first play.

It backfired.

Louisville tried a direct snap to Lamar Jackson after quarterback Reggie Bonnafon went into motion. Petrino said the center was supposed to wait until he received a signal from Jackson to snap the ball. The center didn’t wait.

Jackson was pressured out of the pocket and to his right by Auburn defensive end Carl Lawson. As Jackson neared the sideline, he heaved a pass that was intercepted by former Georgia player Tray Matthews at the 39-yard line. He returned it 35 yards to the 26 as Auburn first-year defensive coordinator Will Muschamp struck the first blow.

“That’s when as a young quarterback you just have to have poise and run out of bounds or get a couple yards and and get out of bounds,” Petrino said. “He threw it up in the air and they got the interception, not at all like we planned or how it worked all week in practice.”

The Tigers capitalized with a 1-yard touchdown run by quarterback Jeremy Johnson to take a 7-0 lead.

Linebacker goes 80 for a score

Auburn capitalized on another Louisville mistake to take a 14-0 lead.

Driving for the potential tying touchdown, Bonnafon didn’t give running back Jeremy Smith a clean handoff, causing a fumble on first-and-10 at the 16-yard line.

The ball squirted out of a pile of players, where linebacker Justin Garrett scooped it up and ran 80 yards — with Muschamp jogging down the sideline with him — for the touchdown to give Auburn a two-touchdown lead with 6:54 left in the first half.

Garrett said they are trained to try to scoop and run if there is nobody around.

“I was just hoping I don’t get caught,” Garrett said. “I was hoping that my teammates would block somebody.”

Louis sprints past Louisville

Auburn’s lead grew to 24-0 on its first series in the second half.

After six consecutive run plays that moved the ball from Auburn’s 25-yard line to Louisville’s 33, Johnson dropped back and rolled right. Ricardo Louis stopped as Johnson moved out of the pocket, but then turned and sprinted past cornerback Trumaine Washington. Johnson hit him with the touchdown pass, his first of the game.

It was one of the few bright spots Johnson had. The junior completed 11 of 21 passes with three interceptions.

“I think he was trying to force a few things, just trying to make some plays early on,” Auburn coach Gus Malzahn said. “He’s going to be fine.”

Cardinals make it a close game

Trailing 31-17 after the team’s traded touchdowns — Auburn’s on an 8-yard run by Louis sandwiched between a 10-yard run by Lamar Jackson and a 2-yard run by Brandon Radcliff for Louisville — the Cardinals pushed Auburn in the game’s final minutes.

Facing fourth-and-7 on the 19, Jackson kept the ball on an option play, ran left and picked up 11 yards to set up first-and-goal at the 8.

On third-and-goal at the 2, Radcliff ran around the right end for a touchdown to cut Auburn’s lead to 31-24 with 2:59 left.

Auburn recovered the onside kick.

Running out the clock

Petrino started the game with a mistake and ended it with a tough decision.

Auburn was called for a holding penalty after rushing for eight yards on third-and-2 at the 38-yard line. Petrino said an official told him that as soon as the ball was spotted on the 48, the clock would start. That forced him to call his final timeout with 52 seconds left. He said he wanted to get the third-down stop and then call it.

Malzahn called a running play and then smartly let the game clock keep ticking, reaching three seconds before taking a delay-of-game penalty.

Instead of punting on fourth down, Johnson rolled right and heaved the ball deep to eat up the game’s final seconds.

“We got up and held on,” Malzahn said.