Two developments — one planned, the other a pleasant surprise — have helped the Boise State wrestling team rebound from an uncharacteristic down season in 2012.

Senior Jason Chamberlain, who redshirted to focus on the Olympic trials, returned to the team this season and is ranked No. 2 in the nation at 149 pounds — adding some much-needed star power to the lineup.

And junior J.T. Felix, a surprising freshman in 2011, used the disappointment of his sophomore season to build a more complete repertoire and ascend to No. 10 in the nation at heavyweight.

The No. 17 Broncos open their home schedule on Sunday against the Sun Devils. It’s the first of five consecutive home duals, through Feb. 13.

“We’re quite a bit better (this year),” coach Greg Randall said. “We knew if we had a good offseason, it would show. Early on, it didn’t show, and I was starting to wonder a little bit.”

The Broncos lost their first four duals of the season. Since then, they have avenged two of the losses in rematches and one in tournament action. They’ve won five of their past six duals, with the loss coming to No. 19 Virginia in the Virginia Duals.

Five Broncos are ranked — Chamberlain, Felix, junior Jake Swartz (No. 12 at 184), senior George Ivanov (No. 15 at 157) and senior Brian Owen (No. 19 at 133).

“When winter break hits is when we really hit it hard,” Felix said. “It’s always good results right out of winter break.”

The Broncos have a lot to prove this year after finishing second in the Pac-12 meet in their home arena last spring and posting a 4-8 record in individual matches at the NCAA meet.

They had finished a school-record ninth at the NCAA meet in 2011 with a senior-laden team. Chamberlain finished third in the nation and is the only remaining standout from that team.

“I never realized they were all a year or two older than me until last year, when I was like, ‘Oh, man, I’m the only one left,’ ” Chamberlain said. “I’ve kind of stepped into the role a little bit of being kind of a leader and helping the young guys when I can.”

Chamberlain split time between the Boise State wrestling room and preparing for Olympic-style wrestling last year. He made the Olympic trials, where he went 2-2, and won the university nationals. He traveled to Finland for the university world meet, but lost in the first round.

He returns to the college level with his sights set on a national title. He’ll have to go through Oklahoma State’s Jordan Oliver, who has moved up two weight classes since beating Boise State’s Andrew Hochstrasser in an NCAA title match two years ago.

“I remember two years ago being an All-American and finishing third, it was really cool … to be on the podium and have 15,000 to 20,000 people cheering for you when you get your award,” Chamberlain said. “But I noticed everyone modestly clapping for the All-Americans and when the national champion got announced, the whole crowd erupted.

“Right then, I said, ‘You know what, nobody cares if you’re an All-American unless you win a national title.’ That’s kind of stuck with me.”

Felix also is driven by the past.

He possesses unusual quickness for the heavyweight division and used that advantage to place second at the conference meet in 2011.

Last year, he dropped to fourth in the Pac-12 and didn’t reach the NCAA meet.

“I came out of nowhere my freshman year,” he said. “Guys didn’t really know who I was or how I wrestled. So my quickness was my key my freshman year. Nobody knew how quick I was. Last year, everybody knew it and I still relied on my quickness — and it didn’t show. This year I definitely was more motivated to have more aspects to my wrestling.”

Felix has improved his conditioning and focused on building the techniques he needs to complement that athleticism.

“He came back in better shape from last summer and kind of developed a style that suits him well,” Randall said. “He’s a lot quicker this year. He could wrestle for 7 minutes. Last year, he couldn’t really give it everything he had for 7 minutes. He’s still getting there, but his progress from last year is unbelievable.”

Chadd Cripe: 377-6398, Twitter: @IDS_BroncoBeat