In less than 11 months, the Detroit Lions' offensive line has been renovated and upgraded in an extreme makeover that has left the unit a low priority in this month's draft.

Through last year's draft and this year's free-agent signings, the Lions have built a starting unit that has a combination of youth, talent and experience. And there's depth in reserve.

General manager Bob Quinn drafted three offensive linemen last year, and two became starters –  Taylor Decker at left tackle, and Graham Glasgow at center and guard. Guard T.J. Lang and tackle Rick Wagner were signed as free agents last month as upgrades on the right side.

The lone survivor in the makeover: Center Travis Swanson is the unit's only full-time starting holdover from 2015.

The bottom line:  It is a good year not to need to use a high pick on an offensive lineman. The draft class, tackles and interior linemen, is not projected to be as strong and deep as in recent seasons.

Lions OL draft priority: Low.

Draft strength: Not a banner year.

Lions' free-agent impact: Strong. Signing Lang and Wagner were upgrades for departing free agents Larry Warford and Riley Reiff.

Detroit Lions OL Draft Breakdown: Depth chart, stats, capsule highlights of the top 5 prospects at OT and the interior, other potential draft candidates and the spotlight player.

Depth chart: Projected starters – LT Taylor Decker, LG Graham Glasgow or Laken Tomlinson, C Travis Swanson, RG T.J. Lang, RT Rick Wagner. Returning backups – G Joe Dahl, Brandon Thomas (2016 practice squad), T Corey Robinson, T Cornelius Lucas III. Addition -- T Pierce Burton.

Top 5 offensive tackles

1. Garett Bolles, Utah: At 6-5 and 297 pounds, he could put on some weight to withstand the rigors of battling in the trenches. He's overcome a checkered background to become a first-round prospect. Bolles played defensive tackle in high school, went on a two-year mission, and attended Snow College in Utah before transferring to Utah. Only one season of FBS competition at Utah makes him a development project, but he has the tools to work with.

2. Ryan Ramczyk, Wisconsin: Ramczyk first enrolled at a technical college in his hometown of Stevens Point, Wis., in what was the starting point of a strange journey that has made him a first-round candidate. He was a one-year starter at Wisconsin in 2016 after transferring from Wisconsin-Stevens Point and sitting out the 2015 season and made first-team All-American. Good size, athleticism and enormous hands (10-7) make him a left tackle candidate in the pros.

3. Cam Robinson, Alabama: A three-year starter at left tackle for the Crimson Tide, Robinson has more size and bulk than the other top tackle candidates in this year's draft. Arm length (35.5) combined with size suits him to play left tackle. Robinson has more big-time experience than Bolles or Ramczyk, and that could push him higher in the first round.

4. Taylor Moton, Western Michigan: Moton started every game for four years after a red-shirt season in 2012. His best position in the pros could be at right guard. Playing in the MAC always raises questions about competition level, but scouts like the way Moton handled himself in WMU's games against Big Ten teams. Moton was a three-sport athlete at Okemos High School – football, basketball and track.

5. Roderick Johnson, Florida State: It's hard not to compare Florida State offensive linemen to Hall of Fame alum Walter Jones. Johnson has the measurables – 6-6.3, 301 pounds and times of 4.90 and 4.91 in two heats of the 40 at his Pro Day. Arm length of 36 inches is ideal for a left tackle. Johnson started the last 31 games at FSU at left tackle and was voted the ACC's top offensive lineman the last two years. Still developing physically, he turns 22 Nov. 28.

Others: Antonio Garcia, Troy; Will Holden, Vanderbilt; Jermaine Eluemunor, Texas A&M; Chad Wheeler, Southern Cal; David Sharpe, Florida; Adam Bisnowaty, Pittsburgh; J.J. Dielman, Utah; Erik Magnuson, Michigan.

Top 5 interior -- guards/centers

1. Forrest Lamp, G, Western Ky.: Moving from his college position of left tackle – where he started 51 straight games – to guard in the pros should benefit Lamp. His body type – 6-4, 309 pounds – is suited to play on the interior. Lamp's Combine workout was impressive – 4.99 time in the 40, 34 reps in the bench press, and a standout in agility drills. He could be the highest rated offensive lineman overall in the draft, but teams might prefer a legitimate tackle over a guard-to-be.

2. Dion Dawkins, G, Temple: Broke in as a freshman starter for a game each at left and right tackle for the Temple Owls in 2013 before a foot injury ended his season. Started his last three seasons. A powerful player with good quickness projected him primarily to guard, but some teams might see him as a tackle.

3. Dan Feeney, G, Indiana: Playing one season of volleyball in high school was an indication of his athletic ability. A four-year starter for the Hoosiers, Feeney started all 12 games at right guard as a freshman in 2012. A foot injury caused him to miss all of 2013. He got some time at right tackle in 2016 because of injuries at that position. He's a solid mid-round prospect.

4. Pat Elflein, C, Ohio State: He's the top-rated prospect in a less-than-stellar crop of centers. Elflein wrestled in high school, which scouts consider a plus because of the skills required to wrestle. After a red-shirt 2012 season, Elfelin was a backup in 2013 and a starting guard the next two years before moving to center in 2016. Strength and intangibles are there for Elflein to have a solid career – and his wrestling background adds to it, as does two seasons as a starting guard.

5. Dorian Johnson, G, Pittsburgh: In 2016 he became the school's first OL to earn All-American honors since Reuben Brown in 1994. Johnson had three starts as a true freshman in 2013 and took over as the full-time starter at left guard in 2014. Built like a tackle – 6-5, long arms, big hands – he has the skill set of a guard.

Others: Isaac Asiata, Utah; Ethan Pocic, LSU; Danny Isidora, Miami (Fla.); Nico Siragusa, San Diego State; Jessamen Dunker, Tennessee State; Ben Braden, Michigan; Nate Theaker, Wayne State.

Spotlight Player: Aviante Collins, TCU: Sometimes the numbers – good and bad – don't compute on where a player is rated, and Collins is a prospect who fits in that category. His Combine workout was eye-popping – 4.81 and 4.77 seconds in the 40, and 34 reps in the bench press to lead all offensive linemen in those categories. He had an up and down career at TCU but finished off his career by starting every game in 2016 at right tackle.