Brock Purdy threw for 307 yards and two touchdowns, and the defense came up with a huge fourth-down stop in the closing seconds as Iowa State upended No. 8 Oklahoma State 24-21 in Ames, Iowa, on Saturday.

Breece Hall scored the go-ahead, 4-yard touchdown run with 5:29 to play for the Cyclones (5-2, 3-1 Big 12).

Will McDonald, the Big 12's second-leading sack specialist coming into the day, recorded back-to-back sacks on second and third down to shut down a late Oklahoma State drive.

But the Cowboys (6-1, 3-1) came up with a stop of their own to get the ball back with 3:18 to play, setting up one last chance.

On fourth-and-2 from the Iowa State 42, Brennan Presley caught a short pass, but was tackled by Kym-Mani King and Isheem Young short of the first down marker, clinching the win for Iowa State.

Xavier Hutchinson had 12 catches for 125 yards and two touchdowns for the Cyclones.

The fourth quarter was a back-and-forth affair. Spencer Sanders threw a 25-yard touchdown pass to Tay Martin with 8:36 to play to give Oklahoma State a 21-17 lead, capping a 5-play, 58-yard drive.

Sanders finished 15 of 24 for 225 yards and three touchdowns.

The Cowboys got on the board first thanks to a short field, driving 48 yards in six plays to take a 7-0 lead on Sanders' 5-yard touchdown pass to Presley with 5:55 to go in the first quarter.

Oklahoma State drove into Cyclones territory on its next drive with an opportunity to extend its lead, but Tanner Brown missed his 50-yard field goal attempt early in the second quarter.

Iowa State took advantage on its ensuing possession, driving 67 yards on 15 plays (eating up 9:35 of clock) to tie the game on Purdy's 1-yard touchdown pass to Hutchinson.

Two possessions later, the Cowboys answered with a 42-yard touchdown bomb from Sanders to Presley, putting them back up 14-7 with 59 seconds to play in the half.

That was the score in the third quarter when Iowa State went on the move again, marching 87 yards in just five plays to tie the game 14-14 on Purdy's second touchdown pass to Hutchinson, this one from 9 yards out.

Cyclones kicker Andrew Mevis broke a 14-14 tie with a 29-yard go-ahead field goal with 2:41 to play in the third quarter.

--Field Level Media