Joe Southwick threw for 335 yards and 2 touchdowns as Boise St. beat Utah St. 34-23

Boise State's Dallas Burroughs (81) is tackled by Utah State's Cameron Sanders (2) during an NCAA college football game, Saturday, Oct. 12, 2013, in Logan, Utah. (AP Photo/Herald Journal, John Zsiray) (The Associated Press)

Utah State's Joey DeMartino (28) gets hit by Boise State's Jeremy Loane (10) during an NCAA college football game, Saturday, Oct. 12, 2013, in Logan, Utah. (AP Photo/Herald Journal, John Zsiray) (The Associated Press)

LOGAN, Utah – Joe Southwick passed for a career high 335 yards and two touchdowns on 30-of-44 passing as Boise State topped Utah State 34-23 Saturday night.

Shane Williams-Rhodes caught 13 of Southwick's passes for 150 yards and a touchdown while running back Jay Ajayi added 109 yards and a touchdown on 22 carries. The Broncos (4-2, 2-1 Mountain West) gained 26 first downs to USU's 16 in the game and gained 447 yards of total offense.

Junior Craig Harrison made his first start at quarterback for Utah State (3-4, 2-1 Mountain West) after Chuckie Keeton, three-year starter for the Aggies, suffered a season-ending knee injury against BYU last week.

Harrison went 7 of 17 for 105 yards and rushed for 36 yards. Freshman Darell Garretson replaced Harrison with 9:23 to play in the third quarter and went 9 of 14 for 116 yards with one touchdown and two interceptions.