Key to Philly's season isn't just QB -- it's the secondary

Bradford, Eagles looking to start season right on MNF (1:51)

Jon Gruden and Mike Tirico preview the first Monday Night Football match up of the year between the Eagles and Falcons. (1:51)

ESPN NFL Insider Mike Sando spends each Sunday with ESPN NFL analyst Jon Gruden and the "Monday Night Football" crew. This week, they're in Atlanta for the Philadelphia Eagles-Atlanta Falcons matchup in Week 1 (ESPN, 6:55 p.m. ET). Here are a few takeaways from Gruden regarding the Eagles' defense.

Chip Kelly's up-tempo offense gets the headlines, and there's no question Sam Bradford is the key variable for the Philadelphia Eagles this season. But succeeding in the playoffs could also come down to sweeping changes the team made in its secondary.

Philadelphia allowed far too many explosive pass plays last season, and there is a clear trend in the wrong direction in that area. It's a problem the Eagles must address to take the next step.

As a head coach, you're looking for your team owner to provide the resources needed to fix these types of problems. Eagles owner Jeffrey Lurie has done that for Kelly by opening his wallet for Byron Maxwell, a very good all-around corner who went to two Super Bowls with Seattle. The Eagles also drafted Eric Rowe, whom I really liked as a safety coming out of Utah, but who struggled in preseason. Philly even signed Walter Thurmond, Maxwell's old teammate from the Legion of Boom in Seattle.

It looks like Kelly got the pieces he wanted to fix a problem that cost the Eagles victories against Arizona and other teams last season. If it all comes together, this defense could become more a part of the solution and less part of the problem. But as this new-look secondary opens against Matt Ryan, Julio Jones and the Falcons' offense on Monday night, there are still questions hanging in the air.