INDIANAPOLIS -- Frank Reich had almost everything as offensive coordinator of the Philadelphia Eagles for each of the past two seasons.

A young quarterback, Carson Wentz, who had emerged as one of the best at his position in the NFL.

A Super Bowl title.

A great relationship with the organization, especially with head coach Doug Pederson.

A franchise that put together a talented enough roster to keep the Eagles among the top teams in the league for years to come.

That's when the almost came into play.

Reich wasn't the head coach -- something he aspired to -- and he knew at the age of 56 the clock was probably ticking on that opportunity.

He didn't hesitate to interview and eventually accept the head-coaching job when Indianapolis Colts general manager Chris Ballard reached out to Reich after Josh McDaniels declined the position in February.

Reich will be back in the city where spent the 2016 and 2017 seasons on Sunday when the Colts play at Philadelphia (1 p.m. ET, Fox).

"It was bittersweet because of a great experience there, such a good relationship with everyone there, but there's only 32 of these things and if it's a goal and aspiration you have to seize the moment, especially because it was Indy," Reich said. "... A lot of times in this business, usually when you are going back some place, you are usually going back to some place you got fired from, and so this isn't like that. I have nothing but great memories and tremendous experience in the two years there. I owe a lot to that organization because they helped give me the opportunity that I have right now to be the head coach here."

Pederson shared the sentiment.

"One, I was happy for Frank that he was getting an opportunity and to be interviewed for that position," Pederson said. "Secondly, selfishly I didn't want him to leave. We had and still have a great relationship, and I was hoping to spend more than two years together. But it's a credit to, one, I think, the success here in Philadelphia, but also the success that Frank will bring to the Colts."

Reich and Pederson talked a lot during training camp, as Reich would ask about running practice, meetings or scheduling things, according to Pederson. And Pederson reached out to congratulate Reich on his first victory -- and celebration dance -- after the Colts beat the Washington Redskins -- last weekend.

Milestones aside, this is a situation where friendships are pushed to the side for the moment as they prepare to compete.

The coaches will basically be looking in the mirror when they go over the scouting reports, because of the history between them. They're both offensive-minded coaches who were quarterbacks during their playing careers.

"You look at them on film and offensively there are some of the same plays that we run, that they're running," Pederson said. "We feel like both teams know each other even though we don't play each other on a regular basis, and of course with our familiarity with Frank, and he with us, I think makes it feel that way."

Reich brought plenty of Philadelphia with him to Indianapolis. He was the offensive coordinator, but Pederson called the plays while the two were together. Nick Sirianni is the Colts' offensive coordinator, but Reich is the playcaller and spends a significant amount of time working with the offensive players.

"A lot of similarities as far as tempo in practice and the games," said Colts linebacker Najee Goode, who played in Philadelphia last season. "Just like with Doug, Frank lets the defensive guys handle the defense without micromanaging things. Then they would come together and meet and see what we have to do to address both sides of the ball."

Reich could easily have been territorial about running the team when it came to the defense, because Matt Eberflus was not his hand-picked coordinator. Eberflus was originally supposed to be on McDaniels' staff, but the Colts honored their agreement and kept him. Reich has given Eberflus freedom to run the defense.

"It's been great," Eberflus said. "I'm just saying, the trust that he has had in me and the trust that he has had in our defensive staff -- really the entire staff -- has been outstanding ... He's trustworthy, respectful, faithful and hardworking. I mean, you talk about a guy in leadership that you would want to have in leadership -- you start naming the qualities -- he has those. So to me, it's just been outstanding to work alongside him, with him and for him. I'm excited about the future."

The biggest thing Reich packed up and brought nearly 700 miles west to Indianapolis was an aggressive offensive mindset, or as Goode described it, being about the "action" when it comes to calling plays.

"He had a lot of belief in the players, and that's where the aggressiveness comes from," Reich said of Pederson. "That's certainly something that I want to portray. I love working with the players. At the end of the day, the players are what make this game so fun -- the things that they can do on the field, the belief and the trust that you have in your players -- and I just think that, that creates the kind of environment and confidence that you want in a football team. That's certainly what we want to do here."