PHILADELPHIA (973espn.com) - The Eagles have a Super Bowl-winning coach comfortable enough to spar with the media and a defensive coordinator who handles the podium like a seasoned politician.

And then there's Mike Groh, the new offensive coordinator elevated after Frank Reich left for a head coaching job in Indianapolis.

There are plenty of questions about the 2018 Eagles, some philosophical like the human-nature aspect of feeling satisfied after success and others more objective like the health of many key contributors, starting with quarterback Carson Wentz, who is still not medically cleared after his ACL and LCL surgery last December.

Maybe the most important hurdle Philadelphia is facing, however, is the loss of Doug Pederson's two most-trusted lieutenants: Reich and former quarterbacks coach John DeFilippo, the new OC in Minnesota who has been replaced by Press Taylor.

Reich has been described as the "voice of reason" by Pederson himself and the steady hand that often steered the "Fearless" Pederson from some reckless decisions while DeFilippo was the man responsible for working with Carson Wentz and Nick Foles on a daily basis, tearing down the offense and rebuilding it with an RPO-heavy tint that Foles became comfortable with on his way to becoming Super Bowl MVP.

Many argue that the beginning of the end of Andy Reid's successful regime in Philadelphia kicked in when he started to lose many of his top assistants to promotions around the league.

By definition Groh and Taylor aren't as good as the men they're replacing and, at least early in the process, their evolution as coaches will be a significant storyline as the Eagles try to repeat as Super Bowl champions.

Groh's first-team offense produced no points in the preseason during 14 drives and was actually outscored by the defenses they faced 10-0. Even adding in the context of what the preseason means and how many players Philadelphia was missing that fecklessness was alarming. Furthermore, the Week 1 starter against Atlanta, Nick Foles had a dismal 48.7 passer rating without Reich and DeFilippo around to put the right buttons in the offense for Pederson to push.

One aspect that was a success in the preseason, however, was the communication.

"It's gone well. Part of the preseason process is to work out communication between the coaches," Pederson acknowledged. "Even the coaches that have been here before, some of the roles have changed, some of the duties have changed on game day offensively based on what we've done in the past."

According to All-Pro right tackle Lane Johnson, offensive line coach Jeff Stoutland, who added run-game coordinator to his duties should be a big help in aiding Groh when it comes to putting the right Easter eggs in the game plan.

"We still have Stout," Johnson said. "He's great at game-planning and a big part of it."

Pederson says the extra moving parts, which also included Duce Staley adding assistant head-coaching duties to his role as running back coach, are all working out well.

"Each week got better and better. The communication is great," Pederson insisted. "Mike does a great job of grabbing information from the staff, then bringing it to me during the course of the game, while maybe I'm on defense, watching and listening to the defensive calls."

There is no game-planning in the preseason of course so Groh can't be called out for any lack of empirical success in August but Foles' issues are solid evidence that the Super Bowl MVP needs coaches who understand what he does well to succeed at a high level. The Eagles had that last season and it's an unknown if they have it again right now.

Groh, though, insists he's not feeling any pressure to fill what looks like some pretty big shoes from the outside, looking in.

"I feel great. I can't wait to get to Thursday," Groh said. "Feels like it's been a long training camp, so we are excited to get there. ... I'm excited about the opportunity just to go out there and get out there and play a real game."

973espn.com Prediction: Falcons 21, Eagles 17

-John McMullen covers the Eagles and the NFL for 973espn.com. You can reach him at jmcmullen44@gmail.com or on Twitter @JFMcMullen