Broncos football operations director John Elway will name his interim head coach Monday morning, before the team convenes for a full-squad meeting at 8:05 a.m.

Team sources say Elway is moving toward naming defensive coordinator Jack Del Rio as the interim replacement for John Fox, who will have heart valve replacement surgery either Monday or Tuesday in Charlotte, N.C.

"I read about it online, and I was surprised," Broncos receiver Eric Decker said of Fox's heart issue. "I didn't know he had prior conditions. It seemed like he was in good health. He always seemed like he was in good spirits. Never seemed like he had an episode. It was hard. He's not only the leader of our team, he really is like a father figure. The way he approaches his job is he makes it fun for us to come in and work for him."

Broncos coach John Fox, left, and defensive coordinator Jack Del Rio, right, have been through many battles together, including at Carolina.
Broncos coach John Fox, left, and defensive coordinator Jack Del Rio, right, have been through many battles together, including at Carolina. (Joe Amon, Denver Post file)

Del Rio has previous NFL head coaching experience, whereas Fox's other two coordinators, Adam Gase and Jeff Rodgers, do not. As of Sunday night, bumping Del Rio up to the interim head coaching spot had not been finalized. Discussions were still being held regarding details such as if Del Rio were named head coach, would he continue in his role as defensive coordinator? Or would another defensive assistant be temporarily promoted?

"I don't know who they're going to pick, but if it's Jack, even though we as an offense haven't spent a lot of time with him, he has a strong presence throughout the building and in the lunchroom," Decker said. "He's always having conversations with guys. He's tried to get to know all the guys. I think that will make it an easy transition if he is picked because he's been there, he's done that."

Providing there are no complications with Fox's recovery, he is expected to miss 6-8 weeks. There is hope within the organization Fox will be able to return to the sideline for the playoffs, providing the Broncos make it.

"Will be back in no time!" Fox said in a text to The Denver Post on Sunday.

Fox led the Broncos to a 28-12 record in 2½ seasons before his heart issues flared up Saturday.

Del Rio was Fox's defensive coordinator with the Carolina Panthers in 2002, then became Jacksonville's head coach from 2003 until 2011, posting a 73-63 record with the Jaguars, which has become more impressive with time. Jacksonville is off to an 0-8 start this season.

With the Broncos on a bye this past weekend, Fox visited with his cardiologist in Raleigh, N.C., on Thursday, and fell ill during a golf outing with family and friends on Saturday in Charlotte, where he has an offseason home.

Fox, 58 was admitted to a Charlotte hospital, and after tests, it was learned he would need aortic valve replacement surgery. Aware he would likely need the heart procedure at season's end, Fox had lost weight and cut out his habit of dipping tobacco this season.

He was in good spirits Sunday and talked extensively with Elway about the temporary plan going forward. He also spoke with each of the Broncos' five captains: Peyton Manning, Wes Welker, Wesley Woodyard, Champ Bailey and David Bruton.

At the conclusion of the team meeting Monday, Decker believes the players will come away with some version of a "let's do it for Foxy" rallying cry.

"No question," Decker said. "I think in a hard situation like this, what he's meant to all of us in that building there's going to be guys fired up to go about our business as professionals. We have good leadership among the coordinators and in the locker room as far as players. I'm not too concerned about the leap we have to make without him."

The Broncos (7-1) play at San Diego on Sunday.

Mike Klis: mklis@denverpost.com or twitter.com/mikeklis