Jalen Jelks' return was a massive boon for Cristobal's Ducks.

While the Oregon football team takes a break from spring practice, we continue with our spring position breakdowns. Today we'll take a peak the defensive line. We'll look back at the 2017 season, look ahead to the new additions and then forecast what we anticipate for the group this fall.

2017 in Review: The big guys up front came to play in 2017, and the youth movement played a big role. True freshman Jordon Scott and Austin Faoliu not only filled in in the middle of Jim Leavitt's 3-4, but excelled there. That paired with upticks in production from ends Henry Mondeaux and Jalen Jelks made way for a breakout season for Joe Salave'a's bunch. Oregon finished second against the run (128.5) in the Pac-12, and fifth in sacks (33) a year after finishing 11th against the run (246.5) and seventh in sacks (25). Mondeaux saved his best for last, finishing with 45 tackles and 5.0 sacks. But, it was Jelks who earned Pac-12 Second-team All-conference honors, totaling 15.0 tackles for loss and 6.5 sacks.

2017 Stats: Jelks — 59 tackles, 15.0 TFL and 6.5 sacks; Mondeaux — 45 tackles, 6.0 TFL, 5.0 sacks; Scott — 34 tackles, 4.5 TFL, 2.0 sacks; Faoliu — 22 tackles, 2.5 TFL, 1.0 sack; Elijah George — 11 tackles, 2.5 TFL; Drayton Carlberg — six tackles, 1.0 TFL; Scott Pagano — six tackles; Hunter Kampmoyer — five tackles; Gary Baker — five tackles; Malik Young — two tackles, 0.5 TFL.

Players Lost: Mondeaux (graduation), George (graduation), Pagano (graduation), Kampoyer (position change).

Players Returning: Jelks (rSR.), Young (rSR.), Carlberg (rJr.), Baker (rJR.), Gus Cumberlander (rJR.), Scott (SOPH.), Faoliu (SOPH.) and Popo Aumavae (rFR.)

Players Added: Miami transfer DJ Johnson. This summer they'll add junior college transfer Sione Vea Kava and prep linemen Andrew Faoliu. Faoliu is the younger brother of Austin Faoliu.

Jordon Scott looks to take on an even bigger role in year two.

Projected Fall Starters: DE — Faoliu, NG — Scott, DE — Jelks

Spring Outlook: Oregon returns three of its top four performers from a year ago. The ceiling is sky high for Jelks, Scott and Faoliu, but this spring will be about identifying who else can contribute. While Baker, Carlberg and Young have each seen action at this level, none has been consistent, and none were real difference makers last fall. Getting at least two of those guys ready might prove integral. Johnson is the wildcard. A former top 100 recruit from Sacramento, Johnson has moved from outside linebacker to end already this spring, and has the talent to be standout. The question will be whether his petition for immediate eligibility is successful. Young is also petitioning to play this year. If it fails, his eligibility clock will be expired.

Biggest Concern: The depth doesn't develop. Injuries have impacted Baker, Carlberg and Aumavae's development (Carlberg and Aumavae have sat the first five spring practices) and eligibility concerns cloud the futures of Johnson and Young. If none are able to provide contributions this year, the guys up front could be in for a long, long year.

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