The Eagles just made an intriguing addition to their inventory at defensive tackle, signing one-time draft darling Charles Walker to a rookie free-agent contract. This, per ESPN analyst Field Yates:

At the start of the 2016 college football season, Walker was drawing praise as a potential early-round pick in the 2017 draft. In August, ESPN's Todd McShay assigned him an early-to-mid second-round grade. As late as November, Mel Kiper had him rated as his sixth-best draft-eligible defensive tackle.

By the time last month's draft rolled around, Walker's stock had tumbled considerably. His decision to leave the University of Oklahoma football team drew considerable attention when head coach Bob Stoops labeled his former player a quitter. At first, Walker cited concussions as the reason he left school. In the run-up to the draft, the player's camp claimed the real reason was a previously undiagnosed battle with depression.

While Kiper was still saying in January he expected the 6-foot-2, 297-pound Walker to go at some point on Day 2, the reality is that Walker ended up giving teams little reason to draft him. He tested abysmally at the combine, finishing near the bottom of the pile in agility drills with middling strength and straight-line speed numbers. His SPARQ score was 44th among defensive tackles, 22 slots behind Eagles sixth-round pick Elijah Qualls, a defensive tackle out of Washington. (In the sports training and testing world, SPARQ is an acronym for Speed, Power, Agility, Reaction and Quickness, with a corresponding formula. In other worlds, it stands for other things.)

Despite a last-minute marketing campaign that included a lengthy testimonial from his doctor, Walker went undrafted.

For the Eagles, he represents an all-upside acquisition along the lines of Dorial Green-Beckham last summer. Walker will have the next four months to try to persuade them to go heavy at defensive tackle in hopes that he develops into a contributor down the line. Fletcher Cox and Timmy Jernigan are ingrained as the starters, with Beau Allen working in as a run-stopping third DT. Walker and Qualls will be competing with 2016 undrafted free agent Destiny Vaeao for reps throughout training camp. The team was intrigued with Vaeao's potential last year, but Qualls and Walker should get plenty of opportunity to persuade them to err on the side of theirs. Recent futures signee Justin Hamilton is also on the roster.