TUCSON, Ariz. — Travis Cobb returned the opening kickoff 95 yards for a touchdown to set the tone for No. 21 Arizona and the Wildcats went on to rout Washington State 48-7 on Saturday.

The Wildcats scored the first seven times they had the ball.

Arizona led 34-0 at the half, then William "Bug" Wright returned a punt 86 yards for a score the first time the Wildcats touched it in the third quarter.

Arizona (6-2, 4-1 Pac-10), the only Pac-10 team never to go to the Rose Bowl, pulled within a half-game of first-place Oregon after the Ducks lost at Stanford. Arizona and Oregon both have one conference loss. Everyone else has at least two.

Washington State (1-8, 0-6) lost its starting quarterback, freshman Jeff Tuel, when he sprained his right knee in the second quarter.

Marshall Lobbestael replaced Tuel and finished 7 of 11 for 103 yards and a touchdown. The Cougars avoided a shutout when Jared Karstetter made a one-handed grab of Lobbestael's pass on a 64-yard touchdown play with 6:23 to play.

Nick Foles threw for 151 yards and a touchdown in limited playing time for Arizona. Matt Scott, the Wildcats' starting quarterback the first three games of the season, rushed for 83 yards in nine attempts and threw for another 26 yards.

Arizona rolled up 471 yards, 294 on the ground. Washington State managed 185 yards — 64 on one play and just 59 rushing.

The Wildcats, in the national rankings for the first time since 2000, were up 14-0 with the game barely three minutes old.

Wright, a 5-foot-9 sophomore, took the opening kick and burst up the left side of the field, racing to the end zone for Arizona's first kickoff return for a touchdown since 1998.

After Washington State went three-and-out, Foles quickly drove Arizona to another score, lofting a 28-yard pass to Terrell Turner to make it 14-0 11:43 left in the first quarter.

Keola Antolin's 19-yard run and a pass interference penalty against Washington State's Brandon Jones set up Arizona's third score. Antolin, starting in place of injured Nic Grigsby, dived over the line from a yard out to make it 21-0 with 7:21 still left in the opening quarter.

The Wildcats led 24-0 after one quarter, then made it 31-0 after Tuel fumbled on a sack by D'Aundre Reed and Arizona's Lolomana Mikaele recovered at the WSU 14. Foles completed a pair of short passes, then Nick Booth scored on a 1-yard run. Booth had 84 yards in 18 carries.

The Cougars then mounted their only drive of the first half, moving from their own 9 to the Arizona 9. A holding penalty moved Washington State back to the 19, then Tuel was hit hard by Xavier Kelley. The WSU quarterback fumbled and Arizona's Ricky Elmore recovered.

Tuel was hurt on the play. He was able to walk off the field but did not return.