When Andy Reid became head coach of the Eagles in 1999, one of the first things he did was construct his coaching staff. To help with the search, Reid spoke to outgoing coach Ray Rhodes about the staff he already had in place. And after speaking with Rhodes, Reid ultimately retained four assistants from the previous regime.

One of those men was now-Ravens head coach John Harbaugh, who brings his team to Philadelphia on Sunday.

Back then, Harbaugh was serving as the Eagles' special teams coordinator. It was a role he would hold capably for nine years. When it became apparent to Reid that his assistant was ready to climb the coaching ranks, he moved Harbaugh to the secondary for a season in 2007. He was promptly snapped up by Baltimore the next year.

For almost a decade, Reid saw in his assistant the qualities he knew would make him successful.

"He's a football coach," Reid explained. "He's a teacher. He's intelligent and a hard worker. He's tough and good with people. Those are qualities that you need to advance as you move up the coaching ladder."

But being a head coach is more than just knowing how to interact with your players. It's also understanding how those players fit together on a team. That means knowing offense, defense and, yes, special teams.

"I think the special teams coach has to deal with both sides of the football (and) as many people as a head coach does as far as it comes to dealing with the football team," Reid said. "Then he had the experience of dealing with the media. Their job is a little underrated in my eyes and then he had the opportunity to move over to the defensive side for one quick shot there."

Harbaugh has certainly had his share of success in Baltimore. He has coached the Ravens into the playoffs each of his four years in Baltimore, winning the AFC North for the first time last season. Under his watch the Ravens have gone 44-20 with a 5-4 playoff record. The rest of the league has taken notice of that success, including the Eagles' own special teams coach.

"Even in Bill Walsh's book, he says it's the best position to move from to be a head coach," special teams coordinator Bobby April said Thursday. "Bill Walsh says that and he had nothing to do with special teams. Of course, he's a smart guy, but he recognized the administrative, the overall, the detail to getting something from every player, getting players to do stuff that they really don't want to do. It's a constant day-in, day-out training on the job to be a head coach."

As for Harbaugh himself, many of the things he learned from Reid – both on and off the field – still make up the coach he is today.

"Andy has been a huge influence," Harbaugh said. "He's been an influence on a lot of guys. A number of guys off his staff have gone on to be head coaches; that's a great testament to how he does things.

"I've got a lot of respect for Andy; I've got a lot of love for his family. We've been pretty close over the years. I have immense respect for what he's done, how he's done it and, sure, it's impacted some of the things we've done here."

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