Washington State is a team known for its potent passing attack, but running back Jamal Morrow emerged as the No. 16-ranked Cougars' hero in a 30-27 upset of No. 5 USC in Pullman, Wash., on Friday.

Morrow, who finished with 91 yards rushing and 47 receiving, took a shovel pass from quarterback Luke Falk 23 yards for a touchdown that put Washington State (5-0, 2-0 Pac-12 Conference) ahead 27-20 in the fourth quarter.

"These are once-in-a-lifetime moments," Falk said in his post-game interview on IMG radio. "Definitely going to enjoy it with the teammates. It was a tremendous, gutsy, team win."

USC (4-1, 2-1) responded when Trojans quarterback Sam Darnold rushed for his second touchdown of the night, capping a drive that freshman wide receiver Tyler Vaughns extended with an acrobatic, fourth-down catch.

But Morrow delivered again on the ensuing Washington State possession, his carries of 11 and 35 yards moving the Cougars into USC territory. Erik Powell's 32-yard field goal proved to be the game-winner, as USC's last-gasp drive ended with Jahad Woods forcing a Darnold fumble.

Washington State matched the final score of its last win over USC (4-1, 2-1) at Martin Stadium. Jason Gesser outdueled Heisman Trophy winner Carson Palmer in that meeting in 2002.

Washington State's ability to convert on third down, and USC's inability to do the same, shaped the course of the game. The Cougars went 8-of-18 on third downs; USC went 2-of-11.

Time of possession played a factor as a result of Washington State extending drives, with the Cougars dominating the ball 35:27 to 24:33. Linebacker Uchenna Nwosu said the Trojans tried to not let fatigue settle in on lengthy Washington State possessions.

"We've got to keep playing. We have guys ready to sub in, so we've just got to be ready to play at all times," Nwosu said in his post-game interview on the USC Trojans Radio Network.

Falk also outperformed Darnold statistically to set the tone for Washington State. The Cougars quarterback finished with 340 yards passing and two touchdowns. The shovel-pass score to Morrow tied Falk with Marcus Mariota as the Pac-12's No. 2 all-time career leader for passing touchdowns.

"It took a tiny bit for us to settle in," Washington State head coach Mike Leach said in his post-game interview on IMG radio. "I thought initially we were just a little too happy that we were in the middle of this thing. But then, once we started to turn it loose ... we started playing better."

Morrow's goal-line touchdown run pushed Washington State into a 17-17 tie at halftime. Morrow's score ended a 12-play, 94-yard drive.

USC running back Ronald Jones II returned from an ankle injury that sidelined him a week ago at Cal to rush for 118 of his 128 yards in the first half, including 86 on a touchdown rush in the second quarter.

Jones' long scoring run answered a Washington State score set up by the Cougars' own explosive play.

Falk found wide receiver Renard Bell open after a USC coverage breakdown, hitting Bell in stride for a 61-yard gain. That led to a 28-yard score on a swing pass from Falk to Tavares Martin Jr.

The touchdown gave Washington State its second brief lead of the first half. The Cougars struck first when a promising, game-opening drive stalled, ending in a 44-yard Powell field goal.

"The first four drives were frustrating," Falk said. "We shot ourselves in the foot. ... That end drive of the first half when we tied it 17-17, that brought a lot of confidence to the guys knowing that we could win this game, should win this game."

Darnold capped USC's opening drive -- 10 plays, 75 yards -- with a 4-yard touchdown rush. The Trojans' next three possessions produced a single first down and ended with two punts and an interception when Sean Harper Jr. undercut a route.

The Washington State defense again came through when a Nwosu interception of Falk set the Trojans up inside the Cougars' 5-yard line. Washington State snuffed out three USC plays, holding the Trojans to a 20-yard Chase McGrath field goal.

NOTES: USC's loss was its first since Sept. 23. 2016 at Utah, which was also on a Friday night. ... USC, which came in without LT Toa Lobendahn, lost RT Chuma Edoga and G Viane Talamaivao to injury in the first half. ... QB Luke Falk's 61-yard pass completion to WR Renard Bell was both Washington State's longest play of the season to date, and the longest play the USC defense allowed. ... USC QB Sam Darnold's eight interceptions this season are one fewer than the nine he threw in the entire 2016 campaign. ... With his 86-yard touchdown rush, USC RB Ronald Jones II has at least one score in 11 consecutive games in which he's suited up dating to last season.