FRISCO, Texas -- It's pregame and Marc Colombo is walking with a purpose.
As the Dallas Cowboys stretch, Colombo makes sure he greets every player with a handshake, a dap or a slap on the shoulder pads. He last played a game in 2011, but the feelings he has before kickoff are the same as when he was in a uniform.
"On game day, he's like a player," Pro Bowl right guard Zack Martin said. "He's got his heavy metal rolling, going around the locker room, yelling and getting everyone fired up. To me, it still looks like he's getting ready to play every week."
A little more than seven weeks ago, head coach Jason Garrett promoted Colombo to offensive line coach, after the team parted ways with Paul Alexander, who was hired in the offseason. It was a somewhat surprising move by Garrett, who had never made an in-season change on his coaching staff since taking the job full time in 2011.
The change was made in part because Garrett and the front office did not like how passive the line had become. The techniques used by Alexander strayed far from what helped make Pro Bowlers out of Martin, Travis Frederick and Tyron Smith, and NFL rushing champs out of DeMarco Murray and Ezekiel Elliott.
Multiple sources inside the organization said Alexander wasn't the right fit.
In Colombo, who played for the Cowboys from 2005 to 2010, they wanted to get back to those roots, but they also wanted his enthusiasm.
"If you've ever been around Colombo even if just for a minute, you feel it," Garrett said. "We felt it as a player. That's one of the reasons why we wanted to bring him into our organization as a coach. He's done a really good job as the assistant O-line coach. A big part of that was bringing that juice, that energy. His connection with the players is outstanding."
After retiring following the 2011 season with the Miami Dolphins, Colombo did not entertain coaching ambitions, but he wasn't quite sure what he wanted to pursue.
"You never really know what you're going to do when you retire," said Colombo, who started 72 of the 76 games he played with the Cowboys in 2005-10. "I knew I needed to lose weight. I needed to feel better. You get 10 years in the NFL, your body is pretty broken down."
He kept his weight at close to 320 pounds during the season to handle elite pass-rushers. He dropped roughly 50 pounds by changing his workouts and doing yoga. He ate better.
He missed the game, but he scratched other interests. Late in his career, he and former teammates Leonard Davis and Cory Procter formed a heavy-metal band, Free Reign, with Colombo as the lead singer.
He took acting classes in Dallas and hired an acting agent. In 2012, he produced and acted in a short film, "Devil Has My Ear," which earned a spot in the Louisiana Film Prize in Shreveport, Louisiana. He worked the Cowboys' pregame show on 105.3 The Fan in Dallas.
"He did always miss playing," his wife, Jessica said. "I know at first it was tough to go back and watch games on TV or even go in person. You do feel like, 'Maybe I can still play,' even after having a successful career. I don't think the acting and the other things gave him that same feeling as playing."
Having seen the hours the coaches put in when he played, he wasn't sure he wanted to put his young family through those challenges, but Garrett held firm on an offer the day Colombo walked away from the game.
"I think he probably realized that the rock-and-roll world and the acting world were a little bit challenging," Garrett said with a laugh. "He and I had a good conversation when he retired. I said, 'You should go pursue those things if that's what you want to do, but know that we want to get you back here at some point.'"
In 2014, Colombo joined the Cowboys' scouting staff as an intern. He worked with personnel chief Will McClay, putting together reports on players. McClay wanted Colombo to experience what the behind-the-scenes-life as a scout was like, and he also wanted his scouts to see what a player sees in breaking down film.
"Doing the radio, the pregame show, I wanted a little bit more and got into scouting," Colombo said. "Did that and wanted a little bit more and got into coaching. That's when I got my foot through the door and I've been in coaching ever since.
"I'm a football guy when it comes down to it."
As it was when he played, he is out the door before his kids, Olivia and Jack, wake up. Unlike when he played, they are asleep most nights when he gets home from work.
"That was probably part of his hesitancy to go into coaching because he did see the hours they worked and having a young family, he felt like he might be missing out on a lot of stuff with the kids," Jessica said. "But that's all they've known. Jack wasn't born when he played. Olivia remembers, but to them this schedule has been the norm. They understand. They enjoy the perks that come with him being involved in coaching. They love going to games. They're at ages that it's kind of a cool thing to see your dad be a coach."
In 2015, he was named the assistant offensive line coach under Frank Pollack. When Garrett decided to move on from Pollack after last season, he interviewed Colombo but settled on Alexander, who spent more than 20 years as the Cincinnati Bengals line coach.
Colombo admitted some disappointment, but he did what he did when he played: He worked.
"I'm a grinder," Colombo said. "That's all I know."
Before Garrett promoted Colombo, he made sure veteran line coach Hudson Houck, who coached Colombo, would return in an advisory role. Houck is there to aid his former right tackle, but Colombo puts the line through the paces each day.
"I think not getting the job just made me more hungry and when it was time to step in, when I got the opportunity from the Joneses and coach Garrett, it was the right time, OK," Colombo said. "It was right time for this team, the right time for this offensive line, the right time to get this thing turned around and going in the right direction."
The Cowboys are 5-2 since the change, with the trade for Amari Cooper being another big reason for the success. Elliott leads the NFL in rushing and has four 100-yard rushing games since Colombo took over.
Things have not been perfect.
Smith missed two games because of a stinger and was replaced by Cameron Fleming. Martin missed the first game of his career last week and his status is uncertain for this week because of a knee injury. Left guard Xavier Su'a-Filo suffered an eye injury against Indianapolis and might not be ready, which could put Adam Redmond in the starting lineup. Colombo has not had Frederick either because of Guillain-Barre Syndrome, but Frederick has taken on a role similar to an assistant line coach, wearing a headset during games.
Dak Prescott has been sacked 28 times in the past seven games -- and 51 times this season -- although that is not completely the fault of the offensive line.
"I just think he's ready to really take the next step of being one of the great O-line coaches in this league," offensive coordinator Scott Linehan said of Colombo.
At 40, Colombo is the NFL's youngest offensive line coach. He said said he uses things he has learned from all of his line coaches -- Tony Sparano, Bill Callahan, Pollack and Alexander -- and added some things he believes work well.
"I know football one way, all right, and that's with passion, energy, emotion and enthusiasm," Colombo said. "That's the way I do it and I have a group that just feeds off that. I love every one of those guys. I'm fortunate to coach those guys and they respond. I coach them hard. We do more detailed technique work than any other unit in the NFL and they just want more and more. That want to get more looks. They want to get more individual time. They feed off that. That's where get our strength from, just outworking everybody."