Boise State sophomore cornerback Bryan Douglas couldn’t deny coach Chris Petersen’s evaluation.

He still didn’t like it.

Petersen told Douglas earlier this year that he was underachieving in the classroom and if he addressed that shortcoming he’d see improvement on the field, too.

Petersen also asked him to increase his intensity in strength and conditioning workouts.

“It was hurtful,” Douglas said. “But I knew as a person, ‘I could be doing better than what I am right now.’ I took it as a challenge.”

That’s exactly what Petersen wanted.

And months later, player and coach are pleased with the results.

Douglas (5-foot-9, 166 pounds) has started the Broncos’ first three games of the season instead of senior returning starter Jerrell Gavins, who has played part time while overcoming last year’s knee injury.

Douglas has made what he calls a “humongous leap” in the classroom.

And he got the reward Petersen dangled in front of him — a new jersey. Douglas never liked the No. 46 he wore the past two years; now he’s in No. 1, one of the most popular jerseys in the program.

“It was nice to have a little bit of a carrot,” Petersen said. “I also told him, ‘You’re not wearing it next year if anything changes.’ ”

That seems unlikely, given the way teammates talk about Douglas’ increased commitment and improved play.

“He came back (this summer) with just a different mindset,” senior cornerback Jamar Taylor said. “The light bulb kind of turned on.”

Added senior wide receiver Mitch Burroughs: “He’s taken a big leap. You can just see the maturity coming out in him. It seems like he’s grown up a lot, in a hurry.”

Douglas learned the game in Los Angeles from two older brothers, including one who has played small-college football.

He met some significant challenges along the way — breaking his clavicle twice and undergoing an appendix surgery in high school.

“I’ve got a great support system,” Douglas said. “My family, my coaches, they’ve been there since day one and they really pushed me to get here.”

He chose Boise State over San Diego State. He visited USC and UCLA and missed a trip to Oregon because of his appendix. He figures he’d have received Pac-12 offers if he hadn’t committed to Boise State early.

The Broncos won him over with their team chemistry.

“There is definitely no other team and no other coaching staff like this one,” he said. “I got to talk to the star players on the team — the guys who were on the side of the building up here at the time. That was something big to me. That’s big to recruits, how some of the top players on the team show love to a kid who’s just in high school.”

That continues when players arrive, with veterans often serving as mentors for the promising youngsters. In Douglas’ case, Taylor has been an influential role model.

Douglas spent this past summer grinding alongside Taylor in extra workouts and asking him questions in the video room.

“He probably got tired of me this summer,” Douglas said. “… It’s going to be hard when that dude’s gone next year.”

By then, Douglas will be in a leadership position.

And he already has a bit of a protégé of his own — true freshman Chaz Anderson, who is redshirting.

The two are cousins.

“I’m the youngest in my family, so I never really had anybody who looked up to me but Chaz,” Douglas said. “I’m just glad he’s here with me so I can show him how things are done around here and hopefully he gets a lot of playing time, too.”

Douglas’ playing time this season comes as a surprise.

The Broncos returned one of the best cornerback tandems in the nation but Gavins, who missed the final 10 games last season, wasn’t a full participant in fall camp.

Defensive backs coach Jimmy Lake said he uses Douglas and Gavins “by feel” during games. Douglas has seven tackles and a forced fumble; Gavins, who started one game as the third corner, has 12 tackles.

“Bryan, he had an opportunity and he took advantage of it,” Lake said. “We had a guy we kind of had to nurse along during camp and sure enough (Douglas) started making plays in camp and we wanted to throw him out there and say, ‘Hey, he’s doing it in practice. It’s got to transition over to the games.’ And sure enough, when those lights turned on at Michigan State, he played really, really well.”

Douglas started one game last year, at San Diego State, when the Broncos faced a crisis-level rash of cornerback injuries.

“I really wasn’t prepared last year,” he said.

Lake has taught him to focus less on the amount of space around him and more on the specific task he needs to accomplish in a given call.

The increased comfort level allows Douglas to use the tools that made him a college recruit in the first place — great speed, solid footwork and uncommon energy.

“Not a lot of guys are going to beat him deep,” Burroughs said.

And with little to distract him off the field, Douglas should get better over the next couple months.

“It’s just less stress when you know your grades are good, you know you don’t have to worry about the weight room,” he said. “Coach Pete always says that everything we do is for a reason. I have no doubt about that saying.”

Chadd Cripe: 377-6398Twitter: @IDS_BroncoBeat