What holes in the roster should the Eagles be most concerned about? Four of our writers weigh in.

Bob Ford

Aside from the usual suspects, I might be alone in worrying a bit about the defensive line. Vinny Curry and Beau Allen combined to take exactly 1,000 defensive snaps last season. That's not nothing. Plus, you have Brandon Graham coming back slowly from ankle surgery and Tim Jernigan unable to start the season because of a back injury. If you've got complete faith in Haloti Ngata and think Michael Bennett still has something in the tank, then my worries are misplaced.

Marcus Hayes

Halapoulivaati Vaitai and Isaac Seumalo are the first two backup offensive linemen. This is a problem.

Vaitai supporters will point out that he played left tackle for two quarterbacks with vastly different playing styles that compelled the offensive coaches to tailor the offense to the each passer. Vaitai performed well enough to help make mobile, dynamic Carson Wentz an MVP candidate. After Wentz was injured, Vaitai performed well enough to help less mobile, less dynamic Nick Foles secure the No. 1 seed in the NFC and win the Super Bowl.

Vaitai's detractors — also known as "realists" — will point out that, among the 79 tackles who took at least 350 snaps last season, Vaitai ranked 61st, according to Pro Football Focus.

Seumalo's supporters will point out that he can play all five offensive-line positions, and played four of them Thursday in Cleveland. Seumalo's detractors will point out that he plays none of them well enough to start.

Depth along the line is so pressing an issue that seventh-round rookie Jordan Mailata should be considered a real option as a front-line backup by midseason. Mailata is a converted rugby player who never played football.

Does this matter? Absolutely. The Eagles used three left guards and two left tackles last season. Offensive-line depth is crucial.

Depth on the line is an issue because of the team's drafting habits. Since 2011, the Eagles have selected only two offensive linemen higher than the fifth round: Lane Johnson, a first-round pick in 2013, and Seumalo, a third-rounder in 2016, when they also took Vaitai in the fifth round.

Les Bowen

We made a big deal, deservedly so, over how many crucial injuries the 2017 Eagles overcame en route to winning the Super Bowl. It was an astonishing feat. Who takes home the trophy without their franchise quarterback, Hall of Fame left tackle and starting middle linebacker? But even so, there were guys whose performances could not have been replaced. If the Eagles had lost, say, Malcolm Jenkins at midseason, would they still have won it all?

I don't think so. And I think that is the case again this season, with Jenkins headed for his 31st birthday on Dec. 20. The Eagles were unable to improve the safety position through the draft. To field a decent third safety behind Jenkins and Rodney McLeod, they eagerly welcomed back 33-year-old Corey Graham on Aug. 5, as soon as Graham decided he wanted to play another year. The fourth safety, once he serves an NFL suspension that will take him out of the opener, apparently will be Deiondre' Hall, acquired from the Bears for a conditional draft pick on cutdown day.

With safety and special-teams ace Chris Maragos still healing from a complicated knee injury suffered last Oct. 12 at Carolina, this is the position on the team with the worst depth. You can argue that the Eagles lack a difference-making linebacker after Nigel Bradham and Jordan Hicks, but Nate Gerry, Kamu Grugier-Hill and LaRoy Reynolds can each step in and do a credible job. We don't know if the Eagles have anyone like that at safety, after Graham.

Zach Berman

The depth at linebacker should be the biggest concern. The Eagles are relying on Nigel Bradham and Jordan Hicks to stay healthy. When they're both in the lineup, there's nothing to worry about. But Hicks' injury history cannot be ignored, and the Eagles don't have an experienced third linebacker as they did with Mychal Kendricks last year. They need only two linebackers on the field most of the time, but injuries (and even a one-game suspension in Bradham's case) mean the Eagles must test their depth.

Kamu Grugier-Hill and Nate Gerry have developed in the Eagles defense, and both converted safeties fit the modern NFL. Still, there will be a drop-off from Hicks or Bradham to either one, and I'm curious to see how that would affect what was the NFL's top-ranked rushing defense last season. If the Eagles are lucky, they won't need to find out.

After linebacker, the depth at defensive tackle is far from a strength until Tim Jernigan returns. Destiny Vaeao and Haloti Ngata are next on the depth chart. Jernigan and Beau Allen combined to play 90 percent of the defensive snaps last season, so that's a huge workload to fill. However, the Eagles will likely play both Michael Bennett and Brandon Graham on the interior – especially on passing downs. That will help.

Of course, when reserve spots are the biggest holes entering the season, it means the Eagles have a good roster.