SEATTLE (AP) _ Brock Huard's first start for the Washington Huskies was one to remember.

Huard, became the first Washington freshman to pass for 300 yards in a game, leading the No. 24 Huskies to a 31-17 victory over Arizona on Saturday.

``Most every time they needed a big throw, he got one,'' Arizona coach Dick Tomey said.

Replacing injured Shane Fortney, Huard, 20, completed 20-of-31 passes for 311 yards and three touchdowns with one interception. He became the 11th Washington quarterback to pass for 300 yards in a game.

Huard passed four yards to Gerald Harris, 24 yards to Jerome Pathon and five yards to Dave Janoski for touchdowns, all in the first half, as the Huskies built a 21-10 lead. He was 15-for-22 for 232 yards in the first half.

Huard is the younger brother of Damon Huard, who became Washington's career passing leader last season while his brother was redshirting.

``It's a lot of fun to continue the tradition Damon set and go after his records,'' Huard said.

``He made some throws out there that were the difference in the game,'' Huskies offensive coordinator Scott Linehan said. ``For his age, it's really phenomenal what he's able to do.''

``His age doesn't tell the story of his ability,'' said Fred Coleman, who caught four passes for 141 yards.

Washington (2-1, 1-1 Pac-10) held Arizona (2-2, 0-1) to 106 rushing yards on 33 carries and the Huskies' secondary intercepted Keith Smith three times, two by cornerback Mel Miller.

Corey Dillon, the Huskies' backup tailback, had his first 100-yard rushing game, getting 125 yards on 20 carries.

Fortney didn't play quarterback because of a strained right knee suffered in the fourth quarter against BYU last week. Wearing a knee brace, he held on the Huskies' extra points and a field goal.

Coach Jim Lambright held Fortney out as a precaution. The Huskies have a bye next week before playing Stanford Oct. 5 at home.

``Shane's fine,'' Lambright said. ``He will be our starter against Stanford.''

Huard was told by his coaches all week to prepare as if he was going to be the starter. He got the official word on Saturday morning.

``It was great for him to come out and establish his own mark on what he can do with this football team,'' Lambright said.

``It's a great start because we won,'' Huard said. ``I know I can execute. I do it in practice.''

Washington took a 31-10 lead with 10 points in a 1:36 span early in the fourth quarter. After John Wales kicked a 37-yard field goal with 3:10 gone in the quarter, Tony Parrish intercepted Keith Smith's overthrown pass and ran it back 45 yards for a touchdown.

Smith passed 17 yards to Jeremy McDaniel for his second touchdown pass of the game midway in the final quarter.

Smith, a redshirt freshman like Huard, was 16-for-29 for 228 yards and two touchdowns, but threw three interceptions.

Size-wise, it was a mismatch. Smith is 5-foot-10, while Huard is 6-5.

``He put the ball on the money,'' Smith said of Huard. ``But us little guys can pass, too.''

Huard completed all six of his passes in Washington's opening 85-yard scoring drive. On the 13th play, Huard rolled left and found Harris 2 yards deep in the end zone.

``Brock marched us down the field and the team just followed his lead,'' Janoski said.

After a 47-yard field goal by Matt Peyton in the opening quarter, the Huskies made it 14-3 with 3:16 gone in the second period as Pathon got behind McAlister for his 24-yard touchdown down the right side.

McAlister got even when he picked off Huard's pass intended for Pathon and returned it 41 yards to the Washington 14 with 5:26 gone in the second quarter to set up Arizona's first-half touchdown. On the Wildcats' first play, Smith found Richard Dice in the end zone for his first touchdown pass.