BRONCOS WITH THE BALL

Chaos on display: San Diego State coach Rocky Long is famous for his 3-3-5 defense, an amoeba style that often confuses linemen and quarterbacks. The Aztecs have 20 sacks and eight interceptions this season. “Sometimes it’s a little bit of dial-a-blitz,” Boise State offensive coordinator Robert Prince said. “We’ve just got to be ready for it all.”

Trending upward: Boise State’s offense has scored at least 32 points in four of the past five games after an ugly start. San Diego State’s defense — particularly the pass defense — has improved greatly in the past four games. The Aztecs allowed 306.4 passing yards per game in the first five games and 197.3 in the next four. “Guys gaining confidence — that was the key,” senior cornerback Leon McFadden said. “Guys were able to hone in and pay attention to assignments.”

AZTECS WITH THE BALL

A new-look defense: Boise State will play without two of its top five defensive backs — starting free safety Lee Hightower (suspension) and No. 3 cornerback Bryan Douglas (knee injury). Redshirt freshman safety Darian Thompson, sophomore transfer cornerback Deon’tae Florence and possibly a true freshman cornerback who had been on the redshirt track are expected to fill those voids. Thompson, who started last week, has played well all season but experience is lacking among the cornerback candidates.

SPECIAL TEAMS

Time for a challenge: Boise State has controlled the special teams action most of the season. Coach Scott Huff expects a test from the Aztecs, who have good speed and solid specialists. “This will probably be our best challenge of the year so far,” Huff said. One interesting matchup: Boise State leads the Mountain West in kickoff returns and San Diego State is last in kickoff coverage.

NOTES

Must-win for Aztecs: San Diego State has won four straight games to get into Mountain West title contention, but at 4-1 the Aztecs can’t afford a loss to first-place Boise State (4-0). “We’re very excited,” San Diego State cornerback Leon McFadden said. “Winning puts more pressure on you. That’s one thing we’re dealing with right now. ... Boise State’s a great team and I have high respect for those guys. I know it’s going to be a battle to the end.”

Staying up late: This is the latest home kickoff in recent Boise State history. The Broncos have started three games after 8 p.m. since 2004, with an 8:15 p.m. start against Oregon in 2009 the latest. “I love it,” Boise State cornerback Jamar Taylor said. “The crowd’s going to go crazy.” The late start accommodates Mountain West TV partner CBS Sports Network.