Pac-12 2015 spring burning questions: Who will replace Mariota among the Pac-12's biggest spring questions

Arizona - Can Anu Solomon take the next step?

The Wildcats certainly had a fantastic season with Solomon under center as a redshirt freshman, winning the Pac-12 South and getting to the Fiesta Bowl. Solomon had a fine overall individual season himself, throwing for 3,793 yards and 28 touchdowns with nine interceptions, but he did not play well in Arizona's final two games of the season which were arguably Arizona's biggest games of 2014.

To me, those struggles in the final two games showed that Solomon is a good quarterback for Arizona to continue winning 7-10 games in a season, but he is going to have to develop into a game changer if Arizona is ever going to become the best team in the conference. That development for Solomon will need to start this spring and I am sure all eyes will be on him in spring football to see if he can start to become that elite quarterback that could take Rich Rodriguez' system and Arizona to the next level.

Arizona State - Can Mike Bercovici become the man?

Bercovici came off the bench when Taylor Kelly went down in 2014 and quickly got Sun Devil fans excited about the future, throwing for nearly 1,500 yards and 12 touchdowns with just four interceptions in limited time. However, stepping in with limited expectations and with defenses unfamiliar with your game is different than coming into a season as a starter with high expectations and that is exactly what Bercovici is facing in 2015. Keep an eye on Bercovici in the spring to see if he starts to look like he is ready to become the leader and star of the Arizona State offense.

Cal - Can a defense start to form in Berkeley?

The Bears got Sonny Dykes' Bear Raid flying high in 2014, but they came up short of making a bowl game because of an abysmal defense. The Bears were the nation's worst in yards given up through the air and amongst the worst in scoring defense in 2014 and it made their offense seemingly have to put up 60 points per-game to win.

Starting this spring, the Bears are going to need to find a way to get their young defensive backs to play better against the pass and somehow get a better pass rush. I am sure that the Bears are hoping that heralded JC corner Antoine Albert and JC defensive end Devante Wilson can come in during the spring and immediately made an impact.

Colorado - Can a defense start to form in Boulder?

The Buffs were a lot like the Bears in 2014 as they got their offense rolling, but their defense was so bad that it was nearly impossible for them to get wins in the Pac-12. The good news is that the Buffs do return a lot of experience returning from the 2014 unit, including a hopefully healthy this year Addison Gillam, who is one of the conference's best when firing on all cylinders. Spring will be important to see if these returning Colorado defensive players can stat to gel more and help get the Buffs back to winning games in the Pac-12.

Oregon - Who replaces Mariota?

All eyes will be on Eugene this spring as a bevy of quarterbacks compete to be the guy who has to replace Marcus Mariota. Returning back-up Jeff Lockie probably has the closest thing to an inside track, but many have said that redshirt freshman Morgan Mahalak could be the next great "MM" in Eugene and incoming freshman Travis Waller has a lot of buzz while coming in early for spring football. Obviously the biggest factor here is if the Ducks will bring in a major transfer to compete with the most likely potential candidate right now being Eastern Washington star Vernon Adams.

Oregon State - What will Andersen change?

The Beavers had become pretty predictable under Mike Riley. A coaching change will be an interesting change in Corvallis and though there will be many interesting individual battles in spring such as the fight for quarterback, simply seeing how Gary Andersen is going to change things up in Corvallis will be the biggest question of spring.

Stanford - Can the defensive line reload?

The Cardinal have had familiar and fearsome faces manning the front of their defensive line for the past few seasons, but 2015 will be a changing of the guard as all three defensive line starters are gone. The Cardinal are going to have to start seeing increased production from reserve contributors like Aziz Shittu, Luke Kaumatule and Nate Lohn along with development from young players like Solomon Thomas who were big time high school recruits.

UCLA - Can Joshua Rosen win the job?

The Bruins signed arguably the nation's top high school QB recruit this year in Joshua Rosen and the highly-touted prospect is going to be competing in spring football. Bruins fans are already hoping that the blue chip recruit can start from day one at UCLA, but he is going to have win the job in the spring and beat out last season's back-up and Texas game hero Jerry Neuheisel.

USC - Can USC finally start living up to expectations?

USC is the land of high expectations and 2008 was probably the last time that the Trojans got close to fulfilling preseason expectations when they were high. This is expected, or actually probably just has to, change under Steve Sarkisian and right away as the Trojans are expected to be a preseason Top 10, maybe even Top Five team in 2015. Obviously there will be no games to gauge whether or not the Trojans are going to fulfill their high expectations, but they will be interested team to monitor in spring to see if the team is starting to gel and rev up in Steve Sarkisian's second spring at USC.

Utah - Can Travis Wilson take the next step?

The Utes took a major step forward in 2014, but their quarterback play left a lot to be desired and I am sure many Utah fans wonder what could have been had they gotten more out of the position. The Utes have the talent and experience returning across the board to have another good season, but whether or not they can continue moving up the conference may hinge on if Wilson can turn into an asset as opposed to a liability. Whether or not Wilson can continued to develop in spring will be a key factor for the Utes along with the health and development of change of pace QB Kendall Thompson.

Washington - Will Cyler Miles remain the starter?

Cyler Miles was the Huskies' starter in 2014 and his stats were fine, but he did very poorly in Washington's make-or-break games and struggled mightily in their bowl game loss. There seems to be chatter that Miles will be competing for his job in the spring against redshirt freshmen K.J. Carta-Samuels and incoming freshman Jake Browning who both have a substantial amount of buzz coming in. Will Miles be able to fight off the youngsters who were handpicked by Chris Petersen?

Washington State - Can a defense begin to form in Pullman?

The Cougars can move the ball through the air, but they simply have a hard time stopping anyone. So much so that defensive coordinator Mike Breske lost his job and Alex Grinch is the new leader of the Cougar defensive unit. Grinch has a hard job ahead of him that he will start to have to take on in spring, especially since the Cougars lost mainstay up front Xavier Cooper early to the NFL. What changes Grinch will make to the Cougar defense and if he can get them gelling during spring will be the big thing to watch in Pullman in the spring.