Iowa State pulled off the biggest upset of the first half of the 2017 season Saturday with a 38-31 win over No. 3 Oklahoma in Norman.

The Cyclones were a near four-touchdown underdog and without starting quarterback Jacob Park after the team announced Friday that Park had taken a leave from the team because of “personal medical concerns.”

Backup quarterback Kyle Kempt, making his first start, threw for 343 yards and three touchdowns and connected with Allen Lazard on the game-winning touchdown with 2:17 left.

While Kempt’s performance was spectacular, so was the play of linebacker and former quarterback Joel Lanning.

Lanning, who began the 2016 season as Iowa State’s starting quarterback, is now the team’s starting middle linebacker. With Park’s absence, he played at linebacker, quarterback and on special teams on Saturday. Lanning was all over the field on defense and was 2-of-3 passing for 25 yards and had nine carries for 35 yards rushing. He also had eight tackles, a sack and a fumble recovery.

It was a performance that Iowa State coach Matt Campbell aptly called “incredible.”

The win breaks an 18-game win streak Oklahoma had over the Cyclones and potentially ruins the hopes of Oklahoma to make the College Football Playoff.

Yeah, it’s Week 6. There’s a ton of football left to be played. But it’s fair to wonder if the Iowa State loss cancels out the potential gain the Sooners got from beating Ohio State on the road earlier in the season. If Oklahoma is compared to other teams with identical records by the playoff committee, it could end up having the worst loss of the group and get left out of the playoff.

If that happens, it’ll be a fate similar to the one experienced by OU’s in-state rival Oklahoma State. In 2011, Iowa State beat Oklahoma State in November to deny the Cowboys a chance at playing for the national championship.

After Oklahoma got that win against Ohio State, quarterback Baker Mayfield planted an OU flag at the middle of Ohio State’s field. Well guess what? Iowa State put an Iowa flag at the midfield logo on Saturday after the game.

Mayfield finished 24-of-33 for 306 yards passing and two touchdowns. While the loss will damage his Heisman hopes, he’s far from having to shoulder the blame for this game. Iowa State scored on its final five possessions after Oklahoma led 24-10.

The game also breaks open the Big 12 regular season title race and — depending on how the afternoon goes — puts TCU in the driver’s seat for the top spot. The Horned Frogs have already knocked off OSU. With a win over West Virginia on Saturday, the Horned Frogs will already be a game up on both Oklahoma teams.

Read more college football coverage from Yahoo Sports:
• Kicker just misses a field goal due to weird rule
• Illinois joins Iowa fans waving to children’s hospital
• Ole Miss falls to Auburn, posts job for head coach
• Miami player rocks the guitar with FSU QB’s leg

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Nick Bromberg is the editor of Dr. Saturday and From the Marbles on Yahoo Sports. Have a tip? Email him at nickbromberg@yahoo.com or follow him on Twitter!

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