The Mountain West is a step behind the American Athletic Conference for the nod as the top Group of 5 league, but this conference has two programs – Boise State and San Diego State – capable of challenging Houston as the top team from the Group of 5 ranks in 2016. After winning the conference and defeating Arizona in the Fiesta Bowl in 2014, the Broncos took a step back in coach Bryan Harsin’s second season. However, the continued development of quarterback Brett Rypien provides plenty of optimism for Boise State to return to the top of the Mountain West. In the West Division, the Aztecs are a heavy favorite and an undefeated regular season mark isn’t an unreasonable expectation.

Boise State and San Diego State are Athlon’s projected top teams from the Mountain West, but Air Force – the defending Mountain Division champion – could knock off the Broncos from the top spot in the division once again. There’s plenty of depth behind Boise State and Air Force, as Utah State, Colorado State and New Mexico should earn bowl bids in 2016. Additionally, Wyoming is expected to take a step forward under coach Craig Bohl.

Nevada and San Jose State are San Diego State’s biggest threats in the West Division, but there’s a considerable gap between the Aztecs and these two teams. Fresno State, UNLV and Hawaii rank in the next tier, with the Rebels trending up under second-year coach Tony Sanchez.

Five Key Questions That Will Shape the Mountain West in 2016

1. Will Boise State Find the Right Answers on Defense?

Scoring points won’t be a problem for the Broncos in 2016. Eight starters return from an offense that averaged 39.1 points a game last season, and this unit will only get better with the development of sophomore quarterback Brett Rypien. Running back Jeremy McNichols also returns after leading the conference with 20 rushing scores in 2015, while top receiver Thomas Sperbeck provides a big-play threat for Rypien after catching 88 passes last fall. The offensive line has to be retooled a bit, but Boise State’s biggest question mark in 2016 is a defense that returns only four starters. The defensive line is new coordinator Andy Avalos’ biggest concern, as this unit was hit hard by departures after 2015. The return of Gabe Perez from injury should help, and junior college recruit Daniel Auelua should push for immediate snaps. However, considering Boise State will have to face a talented group of running backs in 2016 – including a potential matchup against San Diego State in the Mountain West title game – the front line’s development holds the key to the Broncos’ season.

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2. Christian Chapman’s Development at San Diego State

San Diego State isn’t going to stray too far from its formula for success. Rocky Long’s team will lean on its punishing ground attack and defense to contend for another season of 10 (or more wins) and the Mountain West title. Sophomore quarterback Christian Chapman showed promise in limited action last year, finishing 2015 by completing 8 of 11 passes for 113 yards and one score in the Hawaii Bowl win over Cincinnati. While Chapman doesn’t have to be an All-Mountain West quarterback this season, his development could be the difference in San Diego State finishing as a top 25 team or losing to Boise State in the Mountain West title game. The Aztecs also have to find Chapman a few targets on the outside and get more consistency out of the receiving corps.

3. Sorting Out the Middle of the Mountain West

Most of the preseason attention in the Mountain West is likely to surround Boise State and San Diego State. However, the conference quietly has a solid group of teams forming in the next tier after Boise State, San Diego State and Air Force. Utah State, Colorado State, New Mexico, San Jose State and Nevada are all projected to reach at least .500 in Athlon’s predictions. Which of these teams could surprise this fall? Utah State has some significant voids to fill on defense, but the Aggies return a rising star at quarterback in Kent Myers and are led by one of the Mountain West’s top coaches in Matt Wells. Colorado State should improve in coach Mike Bobo’s second year, and there’s a solid core of talent in place on offense despite the loss of receiver Rashard Higgins to the NFL. Nevada should have one of the league’s top offenses, but the defense suffered heavy losses in the front seven. San Jose State and New Mexico took a step forward in the win column last season and another jump in victories isn’t out of the question. Both programs need to improve on defense in order to challenge for a better finish in their respective division.

Related: Grading College Football's New Coach Hires for 2016

4. UNLV…A Team on The Rise?

Making the jump from high school coach to leading a FBS program is no easy task. However, Tony Sanchez certainly proved he is capable of guiding the Rebels. UNLV only won three games but lost four games by eight points or less last season. Additionally, the Rebels improved to No. 105 nationally last year after ranking No. 118 in 2014 in Football Outsiders F+ rankings. More improvement is expected out of UNLV this fall, as the home schedule features winnable games against Wyoming, Fresno State and Nevada, and junior college recruit Johnny Stanton should provide a spark at quarterback. A bowl game is probably a year away, but the Rebels have some positive momentum headed into 2016.

5. Will Fresno State Rebound in 2016?

Tim DeRuyter’s tenure at Fresno State started with 20 wins and a Mountain West title in 2013. However, the Bulldogs have been trending in the wrong direction over the last two seasons. Fresno State is just 9-17 since 2014, and last year’s 3-9 mark was the program’s lowest win total since 1978. DeRuyter wasted no time making changes this offseason, as two new coordinators – Eric Kiesau (offense) and Lorenzo Ward (defense) – provide optimism for improvement. Finding a quarterback is Kiesau’s biggest concern after four players took snaps in 2015, and a new running back must emerge to replace Marteze Waller. On defense, Fresno State returns only four starters, with significant concerns in the front seven. With a schedule that features crossover games against Air Force, Utah State and Colorado State, there’s very little margin for error as DeRuyter hopes to get Fresno State back on track.

Mountain West Conference 2016 Team Previews