Whatever fuel was deposited in the ISU football team’s tank after shutting out Texas in Ames last weekend dried up early in the second half against Oklahoma on Saturday.

Iowa State (3-6, 2-4 Big 12) held the football for more than 33 minutes, turned it over only once and went into halftime with a manageable deficit of 21-9 before No. 15 Oklahoma (8-1, 5-1 Big 12) decided enough was enough.

The Sooners went on to rout the Cyclones by 24 points in the second half, winning the game, 52-16. It was Oklahoma’s 17th consecutive victory in the series.

Despite the OU offense’s eight touchdowns and its accumulation of 684 yards — the second most Iowa State has allowed all season — it wasn’t OU quarterback Baker Mayfield and his offense that ISU coach Paul Rhoads praised first after the game.

“That’s the best defense that we’ve played, by far,” Rhoads said. “They had a lot of free hitters on our ball carriers tonight.”

The OU defense, which allowed only 35 rushing yards to Kansas and 65 rushing yards to Kansas State in two of its previous three games, stifled ISU running back Mike Warren and the Cyclones’ rushing attack all night. Iowa State mustered only 114 yards on the ground, including Warren’s contribution of 43 yards on 18 carries.

Warren fell three yards shy of eclipsing 1,000 yards rushing on the season in his home state of Oklahoma. By doing so, he would have become the first Cyclone to achieve that milestone since Alexander Robinson in 2009.

Wide receiver Allen Lazard, who pulled in eight catches for 101 yards as the offense’s brightest spot Saturday, said his team’s inability to run the ball made moving it through the air equally difficult.

“Their front seven was probably the best we’ve played all year,” Lazard said. “The past few games, we’ve had 200 yards rushing every game, so struggling to run the ball — it makes it harder to pass. They just did a good job of packing the box and just making the right calls.”

The Cyclones ran the ball 54 times and passed it on only 38 snaps against the Longhorns the previous week. But the OU defense forced Iowa State to assume the opposite approach Saturday out of simple necessity — an approach Rhoads mentioned throughout the week as one he feared.

Quarterback Joel Lanning, making his second start of the season, threw the ball 51 times as opposed to 38 team rushes.

Lanning is now 45-for-88 in his first two starts — an efficiency rating Rhoads foresaw as more damaging to his offense’s chances to stay within striking distance against Oklahoma the more his team was forced to rely upon it.

“We didn’t want to get into a pass game with these guys,” Rhoads said. “Part of that is their ability to get pressure on your quarterback.”

Lanning was dropped behind the line of scrimmage four times on the evening, a stat matched, however, by the ISU defense. The Cyclones’ defensive unit managed to contain the nation’s eighth-ranked offense to an extent throughout the first half, but fell short in the areas of tackling and tempo in the second 30 minutes, Rhoads said.

“To beat a team like that, you can’t make many mistakes. You’ve got to tackle a lot better than we did,” Rhoads lamented. “We didn’t play urgent and fast enough against that tempo, [or] have that second and third guy showing up when you needed him to show up.

“[We] gave them too much open field space to play with.”

The Sooners took advantage of the wide-open spaces, namely Mayfield, who threw for 342 yards and three touchdowns. Oklahoma did not produce a 100-yard rusher on the night, but five ball carriers combined to hang 279 rushing yards on the Cyclones — the most they’ve allowed in a game all season.

The road won’t get any easier, as Iowa State hosts No. 5 Oklahoma State next weekend in this season’s final game at Jack Trice Stadium, slated for a 2:30 p.m. kickoff. The undefeated Cowboys toppled No. 8 Texas Christian on Saturday, 49-29, and may pose the greatest test the Cyclones have encountered all season. 

When asked about the Cowboys’ victory against the Horned Frogs, Lazard didn’t blink.

“Not surprised,” he said.

Oklahoma State will be the fifth team currently ranked in the top 25 that Iowa State has played this season, and the sixth ISU opponent in 2015 to hold a ranking in the top 25 for at least one week.