BOISE, Idaho (AP) -- Boise State's offense was efficient and the defense stingy, yet it was the Broncos' special teams that turned the game.
A long kickoff return followed by two long punt returns set up touchdowns that propelled the Broncos (No. 22 BCS, No. 21 AP) to a 42-7 win over San Jose State on Saturday.
Marty Tadman sparked two of the momentum-changing plays, first with a 48-yard punt return to set up a score in the third quarter and then with a cross-field lateral that led to a 44-yard punt return by Orlando Scandrick.
"Special teams can swing a game big-time," Tadman said. "It all leads to field position and field position is huge. When we got it three straight times, that was kind of the clincher."
The Broncos moved to 8-1 overall and 5-0 in the Western Athletic Conference with its seventh straight win, while San Jose State (3-5, 2-3) lost to Boise State for the eighth time in a row.
The Broncos' defense allowed 150 total yards and had three sacks.
Taylor Tharp threw three touchdown passes as Boise State's offense totaled 434 yards and scored 28 straight points after the Spartans closed within seven late in the first half.
Tharp was efficient and effective, picking apart the Spartans secondary with short and long throws. He was 28-of-35 for 259 yards, spreading the ball around to 10 different receivers. His longest was a 44-yarder down the middle to tight end Ryan Putnam that gave Boise State a 14-0 lead in the second quarter.
Freshman Austin Pettis had a career-high seven catches for 54 yards, including a nifty 5-yard grab in the back corner of the end zone that put the Broncos up 35-7 midway through the third quarter.
And Ian Johnson, playing after missing two weeks with a bruised kidney, scored twice but the WAC's leading rusher struggled with 33 yards on 12 carries.
"I felt amazing ... no pain whatsoever," Johnson said. "I was really antsy today to get some more work. I understand the situation and am just glad we won today."
The Spartans have lost three straight.
"There were some good things today, but not nearly enough to be in a game against a good team like Boise State," San Jose State coach Dick Tomey said.
Trailing 14-0, the Spartans marched 72 yards in 12 plays with the help of two penalties on the Broncos. After a pass interference wiped out a Boise State interception, Adam Trafalis tossed a 5-yard TD to Kevin Jurovich to pull within 14-7 with 1:29 left in the first half.
Momentum shifted quickly on the ensuing kickoff when Boise State's Austin Smith ran 51 yards, setting up Boise State deep in Spartan territory. Six plays later, Tharp hit Pettis with a 12-yard strike to put the Broncos up 21-7 with 34 seconds left.
"To me that game is such a lesson to our players," Tomey said. "We got a chance to go into half time down 14-7 and ... special teams failed us again. Then they have two more punt returns in the second half and it's all over."
Top 25 Overview
It was over when... Boise State jumped out to a 14-0 lead early in the second quarter on a 37-yard run by Jeremy Avery and a 44-yard pass from Taylor Tharp.
Gameball goes to... Tharp. Boise State's first-year starting QB had an outstanding day, completing 80 percent of his passes for 258 yards and three touchdowns.
Stat of the game... 14. Both schools had 14 chances on third down. Boise State converted on 10 of them. San Jose State, on the other hand, converted on just two.