Boise State football coach Chris Petersen glanced at the Bronco Stadium grandstands Saturday afternoon and saw something new: a sea of black.

“That was a strange look,” he said, “but I liked it.”

He looked out at the blue turf and saw something that never gets old: suffocating defense.

“It sure helps everybody when it starts with defense,” Petersen said of Boise State’s sixth straight win.

The No. 24 Broncos’ defense did not allow a point, forced three turnovers, battered the quarterback and scored a touchdown in the 32-7 domination of UNLV.

Nike outfitted the Broncos (6-1 overall, 3-0 Mountain West) in black from head to toe for the first Black Out in school history. Senior defensive tackle Mike Atkinson said last week that black is a “dominating” color — and the players hoped to match their play to the look.

UNLV freshman quarterback Nick Sherry, who was averaging 253 passing yards per game, absorbed the brunt of that inspired effort. He hobbled off in the fourth quarter after completing 14-of-31 passes for 71 yards with two sacks, two interceptions and countless hard hits from a relentless defensive line.

“We’ve got a chip on our shoulder,” sophomore linebacker Blake Renaud said. “We just want to prove we’re still a good team even though we lost a lot of players from last year. We’ve got a lot of heart and we like a good fight.”

UNLV finished with 210 yards on 73 plays — a 2.9-yard average — and became the fifth straight Boise State opponent shut out in the first half. Only three plays gained more than 10 yards.

Senior cornerback Jerrell Gavins grabbed an end-zone interception on a terrific, over-the-shoulder catch and returned a fumble 16 yards for a touchdown in a 3-minute, 23-second stretch of the second quarter to stake the Broncos to a 25-0 halftime lead.

“We’re so proud of them,” Petersen said of the defense. “We’ve got some good players out there. I really think the seniors that are out there have taken the next step that we continually talk about. They’re being coached really well. They’ve played well for a while now so they’ve gotten into a good rhythm of what it means to play hard and play team defense.”

The other side of the ball found some rhythm Saturday, too.

Junior quarterback Joe Southwick completed 22-of-29 passes for 243 yards without a significant mistake. His interception came on a Hail Mary to end the first half and several passes were dropped.

The rushing attack added 137 yards, including 55 in the first quarter from senior tailback D.J. Harper. Harper scored two touchdowns and a two-point conversion despite his lightest workload of the season — 12 carries and two catches.

Nine players caught passes, led by sophomore Matt Miller’s five catches for 53 yards and senior Chris Potter’s career-high four catches for 52 yards.

Freshman tailback Jay Ajayi added an impressive 4-yard touchdown run — busting a tackle at the 2 — and sophomore wide receiver Dallas Burroughs hauled in a 47-yard pass in tight coverage.

“It was a little more rhythm,” Petersen said. “Joe did a nice job. He’s getting better and progressing.”

Southwick chipped away at the Rebels in the first half with a bunch of quick hitches to the outside receivers for short gains — plays where he could hand the ball off or throw it outside, depending on the defensive alignment.

He then struck down the field with the bomb to Burroughs and a 35-yarder to Potter on a scramble. Both plays set up short touchdown runs.

Southwick has shown the past two weeks that he’s willing to fire deep down the field if he sees a matchup he likes.

“If it’s 50-50, I’m going to throw it up and let our guys go get it,” he said. “We’ve got some dudes who can go up and make plays.”

The Broncos did miss some opportunities — an issue that has plagued them all season. Backup quarterback Grant Hedrick fumbled on a wildcat play on a promising opening drive (UNLV returned another Hedrick fumble for a TD late in the game) and the Broncos kicked a field goal in the red zone in the second quarter. They also missed a field goal in the second half.

The Broncos have scored 40 points once this season — a total that has been common for more than a decade.

“It’s a little difficult, when you sit there and think about what’s gone on the last four or five years,” Potter said. “But you can see it. We all see it out there. It’s one of those things where we’re slowly breaking through.”

In the meantime, one of the nation’s stingiest defenses has stepped into the spotlight.

“It’s fun to watch,” Southwick said. “Loving their effort.”

The Broncos loved those new-look unis, too.

Maybe enough to wear them again.

“We don’t really (have plans) right at this point,” Petersen said. “But, heck, I think our team would be ecstatic if we made black part of our team colors.”

Chadd Cripe: 377-6398, Twitter: @IDS_BroncoBeat