PULLMAN, Wash. -- The Washington State offense turned the ball over on downs on its first drive against Nevada, but fears of a slow start were soon put to rest when the Cougars scored on each of its five remaining possessions in the first half.

Luke Falk threw for 478 yards and five touchdowns, and No. 18 Washington State rolled to a 45-7 victory over Nevada on Saturday.

Thirteen players caught a pass for the Cougars (4-0). Falk, who was 36 of 47, was replaced by backup Tyler Hilinski in the fourth quarter after Washington State built a 45-0 lead.

Senior running back Jamal Morrow rushed for a game-high 73 yards and also caught four passes for 40 yards and a touchdown for the Cougars.

"Luke (Falk) did a great job of getting a feel for how the defense was playing and what they were gonna give us," Morrow said. "If you're gonna give us the run, we're gonna take advantage of it."

Nevada (0-4) struggled to move the ball. Blake Wright had a team-best 37 yards on five carries and Wyatt Demps caught six passes for 39 yards.

"We didn't mount much of a charge offensively to really get us back in the game, so I was disappointed about that," Nevada coach Jay Norvell said.

Falk began with four consecutive incomplete passes and a sack but was able to shake it off and direct the Cougars to a quick lead. He connected with Tavares Martin Jr. for 52 yards on Washington State's second drive, setting up a 12-yard swing pass to Morrow for a 7-0 advantage.

That opened the floodgates on an overmatched Nevada defense. Washington State scored touchdowns on five consecutive drives.

The Wolf Pack offense faced similar woes. Quarterback Kaymen Cureton faced consistent pressure from the front line as he was sacked four times in the first quarter. Nevada managed 15 yards of offense in the first quarter.

Nevada switched to David Cornwell during the second quarter. Cornwell threw for 33 yards in the first half and guided the Wolf Pack across midfield for the first time midway through the second quarter.

"We need more productive play and leadership at the quarterback position," Norvell said. "I think with a little more leadership and productive play we would be in a different spot as a team."

Nevada's most promising drive of the first half ended like its others, however, as Cornwell was intercepted by safety Jalen Thompson.

Falk then maneuvered the Cougars down the field on another scoring drive, ending with a 6-yard touchdown reception by freshman Jamire Calvin.

Nevada held Washington State to 10 second-half points. The Wolf Pack forced two turnovers in the second half, including an interception by defensive back Nephi Sewell at the Washington State 8-yard line.

"The second half I thought we were more inconsistent as far as how we protected and how we run-blocked," Washington State coach Mike Leach said.

Two plays later, Cornwell returned the favor with his third interception of the day, this one by Thompson.

Nevada broke through with 1:56 remaining as Maliek Broady scored on from the 3-yard line.

NOTES: Washington State QB Luke Falk threw his 100th career touchdown pass in the first half to move into third in Pac-12 history ahead of USC's Matt Leinart. ... Nevada QB David Cornwell, a transfer from Alabama, completed his first pass of the season in the first half. ... Cougars CB Jalen Thompson had two interceptions, giving him three this season. ... Washington State WR Tavares Martin Jr. had his second straight 100-yard receiving game and third of his career. ... Washington State outgained Nevada 560-151. ... The Cougars end a five-game homestand to start the season on Friday night against No. 5 USC.