After Iowa State’s 13-3 loss to Iowa last week, almost all concerns turned toward the Cyclone offense, entering Iowa State’s home-opener against Oklahoma.

This time, the defense faltered. 

A 10-play drive eroded Iowa State’s defensive energy midway through the second quarter, ending with a Sooner touchdown. 

“A lot of it was discipline,” said redshirt sophomore safety Greg Eisworth. “The first quarter, I feel like we did a pretty good job. The second quarter we kind of lost our identity as a defense. We started to regain that in the third and fourth quarter.”

Redshirt sophomore quarterback Zeb Noland and Iowa State’s offense carved out one yard on the Oklahoma defense before punting.

Taking over in its own territory, Oklahoma thrashed the Cyclone defense again. This time, the Sooners moved the ball 74 yards on 10 plays and 4:19 of game time.

The nearly-flawless drive provided no opportunity for Noland, leaving the Cyclones five seconds to operate before halftime.

“Spatially, we weren’t great early in the football game, and it cost us at times,” said Iowa State coach Matt Campbell. “I thought we settled in, linebackers and safeties included. I thought we played much better in the second half than the first half.”

The Iowa State defense marched out onto the field after the break.

On the opening second half drive, the 58,479 fans in attendance on Saturday viewed a defense similar to the Iowa State defense in Kinnick Stadium last week.

Oklahoma running back Trey Sermon fought for three yards on the first play of the third quarter. Kyler Murray completed an eight yard pass to Marquise Brown for the first.

Then, Iowa State’s defense kicked it up a notch. Junior defensive end JaQuan Bailey busted past the Sooner offensive line, wrestling Brown down for a loss of six yards. On second down, redshirt sophomore defensive end Eyioma Uwazurike managed to knock the elusive Murray down one yard behind the line of scrimmage. A Murray incompletion forced a punt and killed some of Oklahoma’s momentum.

After a Cyclone field goal cut Oklahoma’s lead to 24-17, Oklahoma ran its offense back onto the field from its own 33-yard-line. 

The Sooners gained solid yardage on four plays before a De’Monte Ruth personal foul pushed the line of scrimmage to the Iowa State 22.

The defense from the first half reappeared.

Sermon rushed the ball outside the tackles, and Iowa State abandoned wrapping up, with Eisworth bouncing off Sermon on his way to the endzone. The lack of discipline started early in the game. Iowa State missed tackles, took bad angles on ball-carriers and failed to prevent deep passes.

The Cyclones allowed a 48-yard and a 75-yard completion from Murray to Brown in the first quarter. Brown emerged as a thorn in the side of Iowa State’s defense, reeling in nine passes for 191 yards and a touchdown.

Meanwhile, Murray compiled 348 passing yards with three touchdowns and 77 rushing yards. Some of Iowa State’s struggles from Iowa to Oklahoma, may lie in the matchup, too.

Murray — the No. 9 pick in the MLB Draft this summer — brings athleticism Iowa’s quarterback Nate Stanley doesn’t possess. Oklahoma as a whole is quicker, while Iowa’s strategy is grinding down defenses.

“You got to play your defense,” Eisworth said. “You got to make the right reads, you got to be disciplined, you got to cover and you’ve got to cover long. It’s tough, but it’s what you’ve got to do.” 

The Cyclone defense managed to slow down Murray and the Sooner offense, but it was too late. 

Along with chasing down Murray, the Cyclones battled the heat, too. 

At some points of the game, the heat index approached 100 degrees. None of the Cyclones complained after the game, but they did acknowledge it.

Iowa State’s junior running back David Montgomery felt the effects late in the loss.

“It was cramping a tad bit,” Montgomery said. “It was hot out there. I hydrated. I felt like I was over-hydrated, but it still wasn’t enough.”

The Cyclones face a less-daunting offense next week, hosting Akron.