The Pac-12 isn’t short on intrigue for the 2017 college football season. Washington and USC are projected by most to be the top two teams in the league, with Oregon, Stanford and Washington State headlining the next tier. But there’s plenty of depth, as Colorado (the defending Pac-12 South champs), Utah and UCLA are all projected to be bowl teams by Athlon Sports for 2017. The bottom of the league features two teams – Arizona and Arizona State – from the desert looking for improvement on defense, Oregon State is trending up entering its third season under coach Gary Andersen, while California is rebuilding under new coach Justin Wilcox.

What are the 10 biggest storylines surrounding the Pac-12 for 2017? Bryan Fischer examines USC and Sam Darnold, Washington’s quest for a repeat and new Oregon coach Willie Taggart and more:

Pac-12's Top 10 Storylines to Watch in 2017

1. Sam Darnold has USC Back in the Spotlight

It’s hard to overstate just how dire things were at USC a few games into the 2016 season. The Trojans were 1–2 and staring down the barrel of yet another coaching change.

Luckily for head coach Clay Helton, there was an ace up his sleeve in quarterback Sam Darnold. Needing a spark to jumpstart a lackluster offense, Helton turned to Darnold, who made his first start on a short week at Utah. While the game ended up being a close loss, it was clear that the team had a new leader.

The Trojans haven’t lost since, running off nine straight victories, including a triumphant comeback in the Rose Bowl. Darnold’s stellar play down the stretch led USC to a top-three finish and has certainly brought the spotlight back to the Cardinal and Gold. Now he’s a bona fide Heisman Trophy favorite and is even being mentioned as a potential top-five pick in next year’s NFL Draft.

This Trojans team will be a preseason top-10 squad and the consensus pick to win the Pac-12 South. Darnold is a big reason why. After all, if a redshirt freshman can throw for 31 touchdowns and complete nearly 70 percent of his passes, what will he do with another year of experience?

Figuring out the supporting cast will be key for a USC coaching staff that returns largely intact. Ronald Jones II and Aca’Cedric Ware should form a productive duo in the backfield, and five-star freshman Stephen Carr may sneak into the rotation as well. Deontay Burnett, Michael Pittman and Josh Imatorbhebhe figure to take over at receiver for JuJu Smith-Schuster and Darreus Rogers. The Trojans don’t lack talent along a rebuilding offensive line.

It’s likely the Trojans won’t miss a beat. Los Angeles loves an encore, and few seem as well equipped to deliver one as Darnold.

Related: Pac-12 Football Predictions for 2017

2. Huskies Reload for Another Playoff Run

You figured it was only a matter of time before Chris Petersen made Washington relevant again. The Huskies lived up to their preseason hype, winning the Pac-12 and competing toe-to-toe with Alabama — at least for a while — in a CFB Playoff semifinal.

Now, there’s pressure to sustain success. It will be no easy task replacing key players such as speedy wideout John Ross, star safety Budda Baker and versatile defensive lineman Elijah Qualls. That said, the returnees should keep the team in the mix for another conference title. Quarterback Jake Browning is the reigning Pac-12 Offensive Player of the Year and could build on last year’s 43-touchdown effort if he’s fully recovered from shoulder surgery. The Huskies have one of the best tailback tandems in the country in Myles Gaskin and Lavon Coleman, who combined for 17 TDs and more than 2,200 yards last year, and both have the potential be even better in 2017 with the bulk of a deep offensive line coming back. Dante Pettis figures to take over as the top option in the passing game, while Chico McClatcher fills Ross’ shoes as the best bet to stretch the field.

The defense, however, faces some rebuilding. Leading the way up front will be star defensive tackle Vita Vea, who bypassed the NFL Draft and figures to be one of the best defenders on the West Coast. Linebackers Azeem Victor and Keishawn Bierria return in the middle, but the Huskies will need to find a replacement for the underrated tandem of Psalm Wooching and Joe Mathis. The secondary must integrate some new faces, but it’s not as though the Huskies are lacking options on the back end. Sophomore Taylor Rapp may wind up an All-American as he slides into a full-time starting cornerback spot, and safety JoJo McIntosh remains one of the biggest hitters in the league.

Add a top-25 recruiting class to the mix, and it’s clear that Petersen will be able to keep things rolling in Seattle.

3. Life on the Farm After Christian McCaffrey

It says plenty about the Stanford program that 2016’s 10-win campaign felt rather ordinary. Entering 2017, the high expectations remain in place, but Christian McCaffrey will be absent from the backfield. While there have been plenty of impressive players at the position over the years for Stanford, few have been as special as the easygoing star who was on every short list for best player in the sport. While it seemed like he had a somewhat low-key 2016, McCaffrey still followed up his record-breaking 2015 campaign in remarkable fashion considering he missed time due to injury.

Now comes the difficult task of replacing McCaffrey’s astounding versatility. It will likely take a small army to fill the gaping hole he leaves behind on the depth chart.

The team is not without options, however. Bryce Love enters the year as the clear-cut starter at running back and showed what he could do against North Carolina in the bowl game. In addition to being a solid runner, Love isn’t to be overlooked as a pass catcher either, even if his route running is a few ticks behind the guy he’s replacing.

Not to be lost in the shuffle, fellow junior Cameron Scarlett is in line to be the big back grabbing carries near the goal line and in short-yardage situations. Sophomores Dorian Maddox and Trevor Speights will also compete for touches.

After tormenting the Cardinal with a long line of NFL tailbacks across the Bay when he was a coach at Cal, Ron Gould has come on board as the team’s new running backs coach. That will undoubtedly ease the transition in the backfield as the team looks to return to the Pac-12 title game after a one-year hiatus.

Related: Pac-12 Football All-Conference Team for 2017

4. Ducks Chart New Direction Under Willie Taggart

While the uniforms will still be flashy and the offense still super fast, Oregon is a program in transition. After a shocking 4–8 season ushered Mark Helfrich out the door, the Ducks ventured outside their assistant ranks for a new head coach for the first time since 1976.

Enter Willie Taggart, who assumes a new head coaching job for a third time at age 40. The Florida native completed impressive turnarounds at both Western Kentucky and USF but will have his work cut out for him in Eugene. Taggart is no stranger to the West Coast, having helped revive Stanford’s program with Jim Harbaugh, but he returns to a vastly different Pac-12 North.

Things got off to a rocky start. One staff member resigned just weeks into the job after being cited for a DUI, while another on the strength staff was suspended for a few weeks after several players were hospitalized following workouts. Add in a feud with the local media — which was later resolved — and the offseason has been anything but smooth sailing.

That said, there’s still reason to believe things will be much better. Quarterback Justin Herbert flashed plenty of potential as a freshman last year; terrific tailback Royce Freeman is back; and a young offensive line will benefit from the return of left tackle Tyrell Crosby.

The defense is undergoing a significant transformation. Jim Leavitt was brought on board as coordinator after completing a remarkable turnaround at Pac-12 rival Colorado and has nowhere to go but up with the unit.

This much is clear: Things are not like they used to be at Oregon, and that starts at the top.

Related: Order Athlon's 2017 Pac-12 Preview to Get Complete Analysis on the Upcoming Season

5. Josh Rosen’s Return

The Rose Bowl is their home stadium, but the UCLA Bruins have yet to play a “home” game in the postseason under Jim Mora.

Heading into last season, it seemed like it was finally going to be time for the powder blues to make a big run. More than a dozen starters returned for UCLA, recruiting was going well, the defense was loaded and, most important, starting quarterback Josh Rosen was back under center ready to build on an extremely impressive freshman year.

The Bruins pushed Texas A&M and Stanford to the brink in early-season losses but still had the look of a team that could make waves. Then the bottom fell out against Arizona State in early October when Rosen suffered a shoulder injury that would end his season. The team slumped to a shocking 4–8 record that prompted massive changes for Mora’s program — and put the coach firmly on the hot seat in 2017.

Despite all that, Rosen should enter the upcoming campaign with a clean bill of health and a chance to return better than ever. It would surprise no one if he re-emerged as one of the elite QBs in the country in what could be his final season in Westwood. While Rosen may be the centerpiece, UCLA’s success will depend largely on those around him. Tailback Soso Jamabo returns as the team’s leading rusher and has the skill set to contribute in the passing game, but he hasn’t produced the way many expected. The team’s offensive line — long a sore spot for the Bruins — returns mostly intact but needs to improve. Replacing starting tackle Conor McDermott will be key.

Complicating things further is yet another big change on the coaching staff. Mora hired Jedd Fisch to take the reins as offensive coordinator (the third in three seasons), and he arrives from Michigan with a solid reputation for developing quarterbacks. Still, the constant shuffling has to wear on the players and may take a toll early while everybody learns a new system.

Bruins fans probably don’t care as long as the results are there. If Rosen can return to form, a big bounce-back should be in store. This is UCLA we’re talking about, though, so cautious optimism is the best option.

Related: Ranking All 130 College Football Teams for 2017

6. Following Up a Storybook Season in Boulder

Years of football futility washed away in 2016, as Colorado turned in a storybook campaign that resulted in an unlikely South Division title. Not only did CU end an eight-year streak without a bowl game, but the Buffs also spent time in the top 10 and, for a time, even had a slim shot at making the College Football Playoff.

Defending that division title and competing on an equal level with the USCs and Washingtons of the world will test Mike MacIntyre’s skills to the fullest. The Buffs’ offseason has been rather tumultuous and has seen the team lose nearly the entire defensive staff (architects of a top-20 unit nationally), their four-year starter at quarterback and the bulk of the defensive line and secondary.

Not everything is dire in Boulder, though. Much of the optimism surrounds signal caller Steven Montez. The sophomore filled in at times last year and flashed plenty of potential. He led the team to wins over both Oregon schools and posted a respectable 9-to-5 touchdown-to-interception ratio.

Add in seniors Phillip Lindsay (1,252 yards, 16 TDs in 2016) and Michael Adkins II, and the Colorado backfield will undoubtedly be a focal point for the Buffs as they look to sustain success.

Big questions remain on defense with coordinator Jim Leavitt now at Oregon. D.J. Eliot took over after serving in the same position at Kentucky and has plenty of experience running the 3-4 scheme that has brought recent success to the Flatirons. It will be interesting to see who steps up to replace dependable defenders Tedric Thompson, Chidobe Awuzie, Jordan Carrell and Josh Tupou.

But it’s nice to have to deal with expectations once again.

7. Another New Offense has Utah Aiming High

Even after three straight seasons of at least nine wins, there has always been an Achilles heel for Kyle Whittingham’s Utes — the passing game. They’ve gone through offensive coordinators like candy recently (eight in nine seasons), and Whittingham has invested significant recruiting resources into making the team’s passing game a strength rather than the weakness it generally has been.

The latest change came this offseason when Eastern Washington offensive coordinator Troy Taylor took the same job in Salt Lake City. The former Cal quarterback is just two years removed from running a high school program but is highly regarded as an offensive mind and also has Pac-12 assistant experience (at Cal, from 1995-2000). His group led FCS in passing offense in 2016.

Yes, the Utes will continue to run the ball and play strong defense. But you’ll also see elements of former Utah coach Urban Meyer’s offense, plenty of up-tempo concepts and potentially a more consistent passing game with senior quarterback Troy Williams. While Williams’ completion percentage wasn’t anything to write home about, he did make plenty of clutch throws, and expectations are higher with a full spring of tutelage from Taylor. Backup Tyler Huntley could be a dangerous option with a specific package tailored to his skill set. Whittingham will have to locate replacements along the offensive line and for tailback Joe Williams, but given his history, the Utes get the benefit of doubt at those spots.

So with a new season comes another new offense, but after years and years of frustration, there’s plenty of optimism that this time the Utes will figure everything out.

8. Big Changes in Berkeley as Justin Wilcox Takes Over

When it comes to making a coaching change, some subscribe to the theory that going in the opposite direction makes a lot of sense. Cal took that approach when it surprisingly showed Sonny Dykes the door and quickly hired Justin Wilcox to take over in Berkeley. The former Oregon defensive back and recent Wisconsin defensive coordinator knows the conference well from stops at Washington and USC and is fondly remembered for his time as the Golden Bears’ linebackers coach during the high point of the Jeff Tedford era.

The first-time head coach was hired with one goal in mind: fix the defense (or if you can’t fix it, at least make it respectable). The Bears have been dreadful on that side of the ball for years, and it’s safe to say that school brass was tired of seeing the team give up yards and scores in bunches. Wilcox helped the Badgers’ D become one of the best units in the country last season but will have far, far less with which to work at Cal. He’ll have time, though, as the hire was made with a long-term vision of building the program into much more than an occasional bowl team.

Related: College Football 2017 All-America Team

9. Beavers Enter Year 3 of Andersen Rebuild

When Gary Andersen bolted Wisconsin for the Pac-12 outpost of Corvallis three years ago, he was probably shocked to see just how much rebuilding was required. Last season, however, saw a bit of a light at the end of the tunnel. The four wins weren’t much, but anybody who watched the Beavers could see signs of clear progress.

Hopes for this season start with running back Ryan Nall. The mammoth downhill runner emerged during the team’s late-season flourish and nearly hit the 1,000-yard mark despite missing two games. The quarterback position is less settled, but it’s not like the team is lacking options. Darell Garretson started six times last year before going down with an injury, and young Marcus McMaryion showed potential in the second half of the season. Also in the mix is junior college transfer Jake Luton, who certainly looks the part with an impressive arm and the size to match.

Defensively, Xavier Crawford anchors the secondary and gives the team a building block on the back end, but there’s little question that the Beavers need to get better at stopping the run and rushing the passer. That starts with the defensive line, which needs to make big strides if there’s any hope of attaining bowl eligibility.

Taking that next step is never easy, but there’s optimism that the rebuilding job in Corvallis is nearing completion and the wins are soon to follow.

10. Questions Abound for Both Teams in the Desert

It’s easy to forget that both Arizona and Arizona State have won the Pac-12 South in the past five seasons. After the two went back-to-back in 2013 and ’14, many expected the desert schools to be annual contenders for the conference crown in subsequent years.

From that high point, however, the decline has been rapid, culminating in a disastrous campaign last year that saw both teams fail to sniff the postseason. And there’s a lengthy list of questions for both the Sun Devils and the Wildcats entering 2017. First and foremost for both programs is deciding on a starting quarterback.

At ASU, Alabama transfer Blake Barnett figures to be the guy — recent Crimson Tide receivers coach Billy Napier is the new offensive coordinator — but the team has to get more consistent play out of the position.

In Tucson, head coach Rich Rodriguez is hoping that another year of seasoning and off-the-field work will allow a leader to emerge from the duo of Brandon Dawkins and Khalil Tate. The two bring different skill sets to the table, and both showed flashes last year, but one will have to take control at the position.

On defense, coaching transition has been a theme for both schools. Todd Graham brought former Baylor coordinator Phil Bennett to Tempe to run his defense. Arizona DC Marcel Yates returns for a second season to lead a thin group of Wildcats and should benefit from the addition of special teams coach Brian Knorr, who ran Indiana’s defense in 2014-15 and then spent a year at Ohio State.

While neither team will be expected to contend in the division, everybody will be looking closely for signs of progress.