Unranked Iowa State stunningly knocked off No. 3 Oklahoma, 38-31, on Saturday in Big 12 play, fueled by the strong play of quarterback Kyle Kempt.

Kempt, a third-string walk-on QB thrust into his first starting role, threw for 343 yards and three touchdowns — including two clutch go-ahead strikes in the fourth quarter to help seal the upset for the Cyclones (3-2).

Kempt, a senior, had thrown just two passes in his career before Saturday's contest. He played because regular starter Jacob Park went on leave for undisclosed personal medical reasons late this week.

The loss snapped Oklahoma's nation-leading 14-game win streak and the Sooners' 18-game winning streak against the Cyclones that dated to 1990. It was just Iowa State's second victory against Oklahoma (4-1, 1-1 Big 12) since 1961, and the Cyclones (3-2, 1-1 Big 12) did it without their starting quarterback.

ANALYSIS: How the Cyclones beat the Sooners

ISU's road win puts the program in position for a bowl game, while OU's playoff chances were significantly hurt.

Linebacker Joel Lanning was a spark for Iowa State offense, defense and special teams, serving as the team's lightning rod in the win. In the first half, he played 32 snaps on defense, seven on offense and six on special teams.He's the first Iowa State player since 1971 to get significant action both ways in a game. He ran for 35 yards, passed for 25 and had eight tackles, a sack and a fumble recovery.

Oklahoma's Heisman hopeful QB Baker Mayfield threw for 306 yards and two touchdowns in the loss.

Contributing: Des Moines Register, The Associated Press

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