PULLMAN, Wash. -- Washington State quarterback Connor Halliday knew why the Cougars were upset by Colorado on Saturday.
"We've got to quit playing stupid in the second half," Halliday said after the Buffaloes scored three fourth-quarter touchdowns to win 35-34.
Washington State took early leads in games against Eastern Washington and UNLV, then had to survive comebacks to pull out the wins. Against Colorado, the trend finally led to a loss.
"We're a pretty darn good football team when we play together," Halliday said. "We've got to pull a full game together.”
Jordan Webb ran 4 yards untouched into the end zone, the last of the three scores in the final 7 minutes, to lift the Buffaloes over Washington State in the Pac-12 Conference opener for both teams.
"I knew the offensive line was going to block, like they had all day," said Webb, who ran for two touchdowns and threw for two others in the upset. Washington State was favored by 19 going into the game.
Colorado (1-3) had been all but given up for dead after losing its first three games, including last week's 69-14 loss to Fresno State.
"A week ago they were putting the last shovel of dirt on us," said Colorado coach Jon Embree. "I always felt we were better than we were showing.”
Washington State led 31-14 midway through the fourth quarter. Then the Buffaloes scored three touchdowns in the final 7:06 to pull out the win.
Halliday threw four touchdown passes for Washington State (2-2), which was looking for its first three-game winning streak since 2006.
"We're a mentally weak team," WSU coach Mike Leach said. "That's got to change.”
"We want to go complacent when we get ahead and panic when something good happens for the other guy," Leach added. "We are afraid to win.”
It was the third consecutive game in which WSU led in the first half and let the other team close on them in the second. But they managed to hold on in victories over Eastern Washington and UNLV.
Colorado put up 531 total yards, compared to 451 for Washington State.
Webb completed 29 of 42 passes for 345 yards, and was intercepted once. He was sacked six times.
Washington State was ahead 34-28 when Colorado took over on its 30 and marched to the WSU 4. On fourth down, Webb bootlegged up the middle for a touchdown to tie the score. Will Oliver's extra point gave Colorado its first lead, 35-34, with 9 seconds left.
Colorado had pulled within 31-28 on Webb's 70-yard touchdown pass to Nick Kasa midway through the fourth quarter, followed by Tony Jones' 84-yard scoring run with 4:23 left. On the ensuing kickoff, the Cougars wasted Teondray Caldwell's 56-yard return and had to settle for Andrew Furney's 42-yard field goal. That set up Webb's final drive and touchdown run.
The game was played in air thick with smoke from wildfires 200 miles away in central Washington.
Halliday completed 32 of 60 passes for 401 yards and was intercepted twice. Washington State has so far shown only flashes of Leach's high-flying "Air Raid" offense.
Washington State scored on its first possession, when a scrambling Halliday hit Gabe Marks in the end zone with a 32-yard pass for a 7-0 lead. Colorado replied with a crisp 75-yard drive that ended when Webb connected with Nelson Spruce on a 16-yard touchdown to tie the score. Webb completed all five of his passes on the drive.
Halliday was intercepted near the Colorado goal line by Jered Bell on WSU's next possession. Colorado's drive stalled at WSU's 13 and Will Oliver missed the 30-yard field goal attempt.
Marquess Wilson caught a 23-yard scoring pass from Halliday as WSU took a 14-7 lead early in the second quarter.
Colorado fumbled the ball away at its own 39 on its next possession. Halliday's 15-yard touchdown pass to Isiah Myers put WSU ahead 21-7 with 11:48 left in the first half. The drive was kept alive when Halliday hit Myers on fourth-and-8 for an 11-yard gain.
In the third, Carl Winston fumbled deep in WSU territory on the Cougars' first possession, and Terrel Smith picked the ball up on the 10 and ran it down to the 1. Webb ran the ball over on the next play as Colorado closed to within 21-14.
Furney missed a 53-yard field goal attempt for WSU on their next possession.
Daniel Simmons intercepted Webb on the next series, and Halliday threw a short pass to Wilson, who turned it into a 49-yard touchdown reception and a 28-14 lead for Washington State.
A shanked punt gave WSU possession on Colorado's 30, but the Cougars couldn't move the ball and settled for Furney's 45-yard field goal and a 31-14 lead early in the fourth, setting the stage for the Buffaloes' comeback.