ENGLEWOOD — Jack Del Rio's plate remains full even with John Fox back on the job.
Del Rio won three of four games as the team's interim head coach during Fox's November sabbatical for heart surgery.
Denver's defensive coordinator handed the keys back to Fox this week after guiding the Broncos (10-2) into the driver's seat in the AFC playoff race.
"Back at work," Del Rio said after Thursday's practice in 3-degree weather, his to-do list as long as ever.
The Broncos may be in the midst of a season for the ages behind Peyton Manning's 41 touchdown throws and their 38.6-point scoring average, but they're a disturbing minus-4 in turnover differential and Denver's defense ranks 27th in the league.
"I really don't feel like we've played a complete game yet, for whatever reason," Del Rio said. "We're aware we need to play better. I do feel confident that we can play our best football down the stretch here and into the playoffs and that's really what's most important."
During Fox's four-week absence, the Broncos lost four defensive starters, two of them to mysterious ailments.
Safety Rahim Moore underwent emergency surgery to fix a blood-flow problem in his lower left leg and doctors are still stumped over Derek Wolfe's seizure-like episode on the bus ride to the airport Friday.
While his teammates flew on to Kansas City, Wolfe stayed back in Denver along with defensive tackle Kevin Vickerson, who went on IR with a dislocated right hip. Wolfe has yet to be cleared to return to action and doctors remained stumped over what caused him to fall ill.
"Certainly, two of our better guys," Del Rio said. "We'll miss them until Derek is back. We'll miss Vick. He's a good player. But there were some runs that were problematic last week that weren't necessarily a problem of the defensive line."
Linebacker Von Miller has four sacks in the six games he's played since his six-game suspension. He's played just two quarters of the dominant football that was the norm during his first two seasons in the NFL.
Veteran Mike Adams has filled in nicely for Moore, who can return in the playoffs. Dominique Rodgers-Cromartie has been the Broncos' best cornerback with Champ Bailey limited to three games by a nagging foot injury, but Rodgers-Cromartie has missed the last 1½ games with an injured right shoulder.
Bailey returned to the lineup Sunday for the first time since Oct. 20 but was limited to 30 snaps and served as a sideline spectator when the Broncos were making a last-minute stand as the Chiefs drove downfield for a potential game-tying TD. That showed the 12-time Pro Bowler isn't ready for more than a situational role right now.
Del Rio took over the Broncos on Nov. 4, the same day Fox underwent surgery to repair a defective aortic valve. Fox fell ill during the team's bye week while visiting his offseason home in North Carolina. During the bye week, the Broncos had granted Southern California permission to speak with Del Rio about their head coaching job and he interviewed in Denver. That job went to Steve Sarkisian this week.
Del Rio's contract with the Broncos expires after the Super Bowl and it's widely assumed he'll have any number of opportunities to become a head coach in the NFL again, especially after burnishing his credentials like he did last month. Tack on his 3-1 mark with the Broncos to 8½ seasons as the Jaguars' head coach from 2003-11 and he has a career record of 72-73.
"His track record already spoke for itself," Bailey said. "When you're a good coach, you're a good coach. People in this business understand that. And there's only so much you can do to hurt yourself unless you just go off the deep end and I can't see him doing that. He's got his stuff together. He's been good. I know maybe at some point he will be a head coach again.
"But I think he loves what he's doing here right now."
He can add another bullet point to his resume by fixing the defensive deficiencies in Denver down the stretch and helping John Elway hoist another Lombardi Trophy.
Notes: Offensive coordinator Adam Gase on why he didn't wear shorts at Thursday's practice like tight ends coach Clancy Barone did: "Because I'm smarter than that." ... The team's new heating system and practice fields held up well in the arctic blast that dipped temperatures double digits below zero overnight.