The only team to beat Heisman Trophy winner Baker Mayfield and Oklahoma found the antidote to Memphis' high-powered offense Saturday and finished a turnaround season with a road win at the Liberty Bowl.

Sacking quarterback Riley Ferguson six times and holding the No. 20 Tigers more than 200 yards under their per-game average, Iowa State registered a 21-20 win at sold-out Liberty Bowl Memorial Stadium.

Fittingly, it was the defense's ability to create pressure which decided the game. On Memphis' last snap, a fourth-and-10 play from the Cyclones' 40-yard line, Ferguson had to rush a throw toward Phil Mayhue at the right sideline. The pass sailed behind Mayhue with 1:52 left.

Two-way performer Joel Lanning, who notched a sack as a linebacker and also saw time as a quarterback in short-yardage and running situations, sealed the outcome with a 9-yard run for a first down with 1:29 remaining.

"It was team defense, the kind we've been playing all year," Lanning said. "All we did was play one step at a time, one breath at a time, one play at a time."

Tigers coach Mike Norvell said before the game that Iowa State's defense would be the best his team played all year. The final stats bore out that prediction. Memphis entered the day averaging nearly 48 points per game and had allowed just 15 sacks in 12 games.

But the Tigers couldn't keep J.D. Waggoner and JaQuan Bailey out of the backfield. Each had a pair of sacks and combined for three quarterback hurries. Combine that with Memphis' inability to run the ball – it had only 53 yards on 26 carries – and Ferguson had to go it alone.

Ferguson did what he could, hitting 20 of 33 passes for 286 yards and two touchdowns, but it just wasn't enough.

"We really tried to focus during practice and take away how he wanted to scramble," said linebacker Marcel Spears, who bagged 11 tackles and a sack. "We just had to make the plays when they came to us."

Offensively, the Cyclones (8-5) overcame their lack of a running game. Sophomore David Montgomery, who entered the game with 1,094 yards, managed only 52 yards on 24 carries and lost a fumble inside the 1-yard line with 4:06 left in the game that denied them a potential insurance score.

However, Iowa State made up for it with the passing game. Fifth-year senior quarterback Kyle Kempt completed 24 of 38 passes for 314 yards, making liberal use of senior Allen Lazard and Hakeem Butler against a secondary which couldn't find a scheme to consistently cover either one.

Lazard tied a bowl record with 10 receptions for 142 yards, including the go-ahead 5-yard touchdown catch with 4:28 left in the third quarter on which he caught a tipped ball after stepping out of bounds, and Butler added five catches for 111 yards.

It was Butler who started the game with a resounding bang, running free through the middle of the defense and hauling in a 52-yard scoring strike from Kempt just 1:51 into the first quarter.

"My job was just to get the ball to them," Kempt said.

After the Cyclones' quick strike, the Tigers (10-3) equalized with six minutes left in the first quarter on Ferguson's 10-yard touchdown pass to Anthony Miller. But Iowa State regained the lead with 4:28 remaining in the first half as Lanning scored on a 2-yard run.

Riley Patterson's 34-yard field goal on the half's last snap drew Memphis within 14-10. The Tigers took their first lead of the day just 1:38 into the third quarter. Ferguson hit Mayhue with a short pass down the right sideline and the senior slalomed through defenders for a 36-yard touchdown.

Patterson answered Lazard's touchdown with a 30-yard field goal at 2:16 of the third quarter. But Memphis couldn't solve the Cyclone defense for the day's remainder, giving second-year coach Matt Campbell another signature win to go along with the ones over Oklahoma and then-unbeaten TCU.

"The standard has been raised," he said. "Something special is brewing."

NOTES: Memphis RB Darrell Henderson (hamstring), who led the team with 1,154 yards rushing and averaged 8.9 yards per carry, didn't play. ... Iowa State played without senior defensive backs Evrett Edwards (ineligible) and Kamari Cotton-Moya (violation of team rules. Edwards started nine games this year and notched 51 tackles, while Cotton-Moya registered 60 tackles and three interceptions in 12 games. ... Tigers WR Anthony Miller's third quarter reception enabled him to break his single-season school record for most catches in a year with 96.