MEMPHIS, Tenn. (AP) -- Louisville and Memphis combined for 105 points, 1,202 yards of total offense and 15 plays of more than 20 yards.
But it was the shortest of runs -- a 1-yard touchdown by Eric Shelton with 37 seconds left -- that proved to be the difference Thursday night as Louisville (No. 16 ESPN/USA Today, No. 14 AP) escaped with a 56-49 victory.
"It was a good thing we had a lot of weapons," Louisville coach Bobby Petrino said. "It was exhausting. It was a full day's work."
The Cardinals (6-1, 4-0 Conference USA) came in with the nation's top-ranked offense. They gained 599 yards, 92 yards more than their average but 4 less than the Tigers (5-3, 2-3), who nearly beat a ranked opponent for the first time since 1996.
Shelton ran for 136 yards and four touchdowns on 14 carries, including a 78-yard TD in the second quarter. But his three short touchdown runs in the second half were the key.
"Every time we got on the field, we had the ability to score," Shelton said.
Louisville quarterback Stefan LeFors, the nation's most efficient passer, wasn't as sharp as his 76 percent season completion rate, but he still hit on 24-of-34 attempts for 321
yards and three first-half touchdowns without a turnover.
It was a wild game that featured 10 lead changes, capped when Shelton scored from the 1 to put the Cardinals ahead 54-49. LeFors ran in a 2-point conversion and then Louisville's Abe Brown intercepted a pass to seal it with 21 seconds left.
"It was a big night for us on the national stage. We earned the right to be here," Memphis coach Tommy West said. "When we had them on third down, we could not stop them. Tonight I think we just got whipped on defense."
Louisville, which was 9-for-13 on third-down conversions, took a 48-40 lead after consecutive touchdown runs by Shelton, the second with 11:54 remaining.
Memphis answered when Danny Wimprine, who threw for four touchdowns and 361 yards, ran in from the 1 to make it 48-46. The Tigers failed on a 2-point conversion attempt that would have tied the game.
But the Memphis defense got a key turnover when Shelton fumbled a handoff with 7:36 left, and Wimprine went back to work on the Tigers' 39.
He led his team to the Louisville 9, but after a penalty, two incomplete passes and a 2-yard run by DeAngelo Williams, Memphis settled for Stephen Gostkowski's 29-yard field goal and a 49-48 lead with 6:20 left.
That was plenty of time for LeFors, who gave the Cardinals their seventh play of more than 20 yards when he found J.R. Russell for a 28-yard completion to the Memphis 27. Russell finished with 146 yards and two TDs on seven catches.
"The offensive line did a great job of giving me time, J.R. made a great catch," LeFors said.
The Cardinals then ran the ball four straight times as the clock ran down under a minute, and Memphis couldn't stop Shelton from scoring the winning touchdown.
The second half was downright slow after a frantic first half that featured a combined 68 points and 703 yards of total offense.
The teams scored on five consecutive drives, and there were only two punts -- on the Cardinals' first and last possessions of the half.
Louisville came in with the nation's 11th-ranked defense, but the Cardinals gave up 17 first-quarter points after allowing just one touchdown in their first six games.
LeFors bailed the defense out after the Tigers took a 24-14 lead on a 31-yard TD run by Williams, who finished with 200 yards on 26 carries.
LeFors found Russell diving across the goal line for a 32-yard TD pass, and the defense got into the act when safety Kerry Rhodes stripped Williams on third-and-20 and returned it 40 yards for a touchdown to make it 28-24.
"He got a big bounce and it bounced right into his hands and he took it the distance," Williams said. "He told me after he took it the distance, 'Hey, thanks for the touchdown.'"
Memphis, looking to become bowl eligible for the second straight year, wouldn't go away easily. Wimprine found Tavares Gideon for touchdowns on consecutive possessions -- the first to cut the deficit to 35-33 before halftime and the second to give Memphis a 40-35 lead in the second half.
That's when Shelton took over, scoring on Louisville's next two possessions sandwiched around Memphis' only punt.