PULLMAN, Wash. -- Andrew Luck threw two third-quarter touchdown passes to Levine Toilolo as No. 7 Stanford beat Washington State 44-14 Saturday to extend the nation's longest winning streak to a school record 14 consecutive games.Stanford (6-0, 4-0 Pac-12) struggled against the Cougars defense before blowing the game open in the second half. Luck, among the leading Heisman Trophy candidates, finished with four touchdown passes, all in the second half.Washington State (3-3, 1-2) hoped to get a boost from the return of quarterback Jeff Tuel. But they had little success against a Stanford defense that is allowing just 10 points per game.Luck completed 23 of 36 passes for 336 yards with one interception.Tuel, who fractured his collarbone on his first series of the season, finally was cleared to play and started the game in place of reserve Marshall Lobbestael. He completed 17 of 30 passes for 145 yards.The Cougars generated just 257 yards of total offense in the game, to 475 for Stanford.Leading 10-7 after the half, Stanford drove 85 yards on its first possession of the second half, with a 62-yard pass play from Luck to Coby Fleener covering most of the distance. Luck fired a 10-yard touchdown pass to Toilolo for a 17-7 lead.After punting on its next series, Stanford scored on a 62-yard drive late in the third when Luck hit Toilolo for a 26-yard scoring pass and a 24-7 lead. Luck also fired an 8-yard scoring pass to Stepfan Taylor and a 28-yard touchdown pass to Fleener in the fourth.Lobbestael scored on a short run for Washington State.In the first half, Jordan Williamson kicked a 23-yard field goal with 1:34 left in the first quarter to give Stanford a 3-0 lead. The Cardinal have not been scored on in the first quarter all season.Washington State's Jared Karstetter caught a pass from Tuel but fumbled after he was hit at midfield. The ball was scooped up by Stanford's Michael Thomas, who ran down to the Cougars' 20. On 4th-and-goal from the 1, Jeremy Stewart bulled over to give Stanford a 10-0 lead midway through the second quarter.Stepfan Taylor fumbled on a run and Chester Su'a recovered for Washington State on Stanford's 40. Aided by two pass interference calls on plays to Karstetter, the Cougars drove to Stanford's 2. Carl Winston ran up the middle to cut Stanford's lead to 10-7 at the half. It was the fewest points either team has scored at the break this season.Luck had just 89 passing yards in the first half, on 10-of-16 passing, and the Cardinal had just 165 yards of offense. Washington State was held to 94 yards of offense in the first halfThe Cardinal lead the Pac-12 in rushing defense, total defense, scoring defense and sacks per game. They have allowed just six points in the third quarter all season.