Guy with two TDs faces near impossible job of replacing Marcus Mariota

After spending three seasons in Marcus Mariota's shadow, Jeff Lockie (left) has a shot to step into the spotlight in Eugene.

Scott Olmos/Scott Olmos-USA TODAY Sports

The Pac-12 has made significant progress in catching the SEC in overall conference hierarchy over the last few seasons and is one of the deepest leagues in the nation. However, all of the expected frontrunners have key personnel voids to fill in 2015. Here are the toughest jobs on the market.

5 PLAYERS REPLACING PAC-12’s BIGGEST NAMES IN 2015

Jeff Lockie: Rising junior QB, Oregon

Replacing: Marcus Mariota, 2014 Heisman Trophy Winner

There’s no doubt Lockie has the biggest shoes to fill of any player on this list. Needless to say, following a Heisman winner and replacing Marcus Mariota’s production will be nearly impossible for the Ducks in 2015. The quarterback battle in Eugene is up for grabs, but Lockie has to have a slight edge based on his experience for the last two seasons as the backup. In his brief Oregon career (2013-14) Lockie has completed 29-of-41 passes for 264 yards and one score, while adding 32 yards and one touchdown on the ground. Although Lockie enters the spring at the top of the depth chart, the battle to replace Mariota is far from finished. Freshmen Travis Waller and Morgan Mahalak are expected to push for time, while sophomore Ty Griffin is eligible after sitting out 2014 due to NCAA transfer rules. Could the Ducks pursue a graduate transfer?

Kyle Murphy: Rising senior OT, Stanford

Replacing: LT Andrus Peat, first-team All-Pac-12 (2014)

Stanford’s Kyle Murphy.

Replacing: Danny Shelton, first-team All-Pac-12 (2014)

Replacing Danny Shelton’s production from the nose tackle position (93 tackles, 16.5 TFL and nine sacks) will be a tough assignment for coordinator Pete Kwiatkowski. Shelton was a key cog in a rush defense that held Pac-12 opponents to 125.5 yards per game in 2014. He was also selected to the Athlon Sports first-team All-American squad and earned first-team All-Pac-12 honors in 2014. Needless to say, Qualls has big shoes to fill in replacing the 339-pound nose tackle. In 14 appearances last season, Qualls recorded 13 tackles (two for a loss) and registered one quarterback hurry. Washington’s defensive line needs the No. 116 recruit in the 2013 247Sports Composite rankings to emerge as a force in 2015.

Huskies’ Elijah Qualls.

Josh Rosen: Incoming freshman QB, UCLA

Replacing: Brett Hundley, second team All-Pac-12 (2014)

A true freshman quarterback starting for UCLA? It’s certainly possible next season. Brett Hundley capped a standout career with the Bruins by recording second-team All-Pac-12 honors in 2014. He threw for at least 3,000 yards in each of his three years at UCLA and tossed 75 touchdown passes to just 25 interceptions. The battle to replace Hundley will begin this spring, with Jerry Neuheisel and Asiantii Woulard competing with Rosen for the starting job. Neuheisel has the edge in experience, but there’s a clear talent edge to Rosen. The California native ranked as a five-star prospect and the No. 12 recruit in the 247Sports Composite and enrolled in time to compete in spring practice. How quickly can Rosen get acclimated to the collegiate level? If he picks up the offense this spring, there’s a good chance he takes the first snap for the Bruins in 2015.

Highly touted QB recruit Josh Rosen.

JuJu Smith: Rising sophomore WR, USC

Replacing: Nelson Agholor, first-team All-Pac-12 (2014)

USC is pegged as the early favorite in the Pac-12 South, but for coach Steve Sarkisian’s team to claim the conference title, the offense has to find a replacement for standout receiver Nelson Agholor. Smith is one of the Pac-12’s rising stars and caught 54 passes for 724 yards and five scores in his first season with the Trojans. The California native was a five-star prospect in the 2014 247Sports Composite and may play a few snaps on defense next year. Regardless of whether Smith is on offense or defense, he’s one of USC’s top playmakers and will play a key role in replacing Agholor.

USC’s JuJu Smith takes off.

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