We continue our team-by-team preview in the Pac-12. Up next, the UCLA Bruins.

2015 record: 8-5 (5-4 Pac-12)

2016 FPI preseason rank: 17

2016 FPI win projection: 9.0-3.5

FPI chance to win the Pac-12: 29.1 percent

FPI chance to win the Pac-12 South: 49.1 percent

Key losses: DT Kenny Clark, LB Myles Jack, OT Caleb Benenoch, RB Paul Perkins, WR Jordan Payton, LB Aaron Wallace, WR Thomas Duarte, WR Devin Fuller, C Jake Brendel

Key returnees: QB Josh Rosen, LT Conor McDermott, DL Eddie Vanderdoes, LB Jayon Brown, DE Takkarist McKinley, S Randall Goforth, S Jaleel Wadood

If Josh Rosen steps up as a sophomore, UCLA could be the team to beat in the Pac-12 South. Jae C. Hong/AP, File

Most important player: Rosen. Forget just UCLA -- Rosen is the most important player in the Pac-12 and maybe the country. Take him off the Bruins and few would consider the Bruins a conference-title favorite, but with him that's exactly what they are. Backup quarterback Mike Fafaul, a fifth-year senior and onetime walk-on, has looked good in training camp, but the difference between him and Rosen is substantial.

Impact newcomer: WR Theo Howard. After losing three receivers to the NFL draft, UCLA has a lot of production to replace. Howard should play a big part in filling that void. Throughout training camp, Howard's teammates have been extremely complimentary of the true freshman, and the expectation is for him to make a real impact from Day 1.

Breakout player: McKinley. He has set the bar high for himself. McKinley said the team's shift to a predominantly 4-3 base defense will allow him to "show why I'm going to be the best pass-rusher in the country." That might be a bit extreme, but McKinley has the physical traits to be among the best pass-rushers in the Pac-12, and a double-digit sack total wouldn't come as a surprise. After arriving during the season in 2014 and playing somewhat out of position on the interior last year, he's at home at defensive end this season.

Position unit of strength: Defensive backs. Three starters -- Wadood and Goforth at safety and cornerback Fabian Moreau -- have been second-team All-Pac-12 selections in the past and headline one of the best defensive backfields in the country. After a strong 2015 campaign, Marcus Rios will start opposite Moreau. Adarius Pickett could step in and the defense wouldn't miss a beat.

Position unit of weakness: Receiver. Weakness is relative here because the Bruins could turn out to be very strong at receiver. But, for now, it's the position group with the least amount of clarity. As noted above, the departures to the group will free up opportunities for players who haven't been called upon to be major contributors in the past.

Biggest remaining question mark: Scheme, scheme, scheme. Both sides of the ball have undergone significant transformations, so it will be interesting to see how the Bruins look come Sept. 3 in the opener against Texas A&M. The offense has ditched the spread up-tempo offense former coordinator Noel Mazzone preferred in favor of a somewhat multiple attack under Kennedy Polamalu. It's a better fit for the Bruins' personnel -- specifically Rosen -- and was done in part to help the defense become better suited to go up against power teams such as Stanford.

Most important game: Stanford, Sept. 24. Head coach Jim Mora still hasn't beaten Stanford, and the Cardinal own an eight-game winning streak against UCLA that dates back to 2009. If UCLA can open its Pac-12 schedule with a win over the defending champion, it will be in the driver's seat in the Pac-12 South. From there, UCLA has a favorable schedule leading into its game against USC at the Rose Bowl on Nov. 19.

Upset watch: Nov. 3, at Colorado. The Buffaloes gave UCLA all it could handle at the Rose Bowl last season, and with an improved team, they could provide a stiff challenge in Boulder on a cold Thursday night.

Best-case scenario in 2016: 11-1. The Bruins have all the pieces they need to challenge for a College Football Playoff berth, but it's hard to imagine an undefeated season after the team sputtered down the stretch last year.

Worst-case scenario in 2016: 5-7. It doesn't take much of an imagination to envision a 1-3 start: lose at Texas A&M, beat UNLV at home, lose at BYU, lose to Stanford at home. If that happens, a .500 record over the final eight games wouldn't be out of the question, causing the Bruins to miss a bowl.

Prediction: 9-3. It’s a good year to miss Washington and Oregon, but even with the conference schedule on UCLA's side, the Pac-12 figures to bring a surprise or two along the way. There's a lot to like about the Bruins ... just as there was last year. They'll be better, but they'll still fall just short of that elusive conference title. Rosen has a good chance to establish himself as the best quarterback in college football, which would set up massive expectations going into 2017.