FLORHAM PARK, N.J. -- New York Jets defensive coordinator Kacy Rodgers missed practice Friday because of an undisclosed health condition. He will not coach in Sunday's game against the Broncos, a source confirmed to ESPN.

Coach Todd Bowles was visibly shaken when he announced the news to the media on Friday.

"He's a tough guy," Bowles said. "It's a serious thing."

Rodgers, 49, coached practice Thursday, but skipped his weekly media session because of a doctor's appointment. On Friday, he wasn't at the facility.

Bowles didn't provide any specifics as to the nature of Rodgers' condition, simply saying, "He's ill. We can't discuss it now. We'll see going forward where he is, and we'll go from there."

Earlier in the day, Bowles made the announcement to the team. Several players said Bowles was somber when he broke the news. He didn't share specifics in front of the team.

"He has a heavy heart," tackle Kelvin Beachum said of Bowles.

Bowles and Rodgers are close friends, having coached together previously with the Dallas Cowboys and Miami Dolphins. When Bowles was hired by the Jets in 2015, he named Rodgers his defensive coordinator.

"Obviously, we're all thinking about him," defensive end Henry Anderson said. "All of us were hit pretty hard when we heard the news. He's such a good dude. I'm hoping everything works out and he's back as soon as he can. We miss him, for sure."

Rodgers was the defensive playcaller. Bowles will handle that responsibility when the Jets (1-3) face the Denver Broncos at MetLife Stadium.

Bowles will be without one of his top players, as cornerback Trumaine Johnson was ruled out with a strained quadriceps. He was injured Thursday in practice, and the early indication is that he could miss multiple games.

Asked if it's a potentially season-ending injury, Bowles said, "Not at this time, no."

The Jets probably will move nickelback Buster Skrine into the starting lineup, opposite Morris Claiborne. When they play nickel, Skrine will slide inside to the slot, his customary spot, with Darryl Roberts playing on the outside with Claiborne.

"Anytime you lose a starter, it's a big deal, but we have guys who have played the last couple of years that we like -- Roberts, Buster, [Parry] Nickerson, as well as [Juston] Burris," Bowles said. "We'll go from there. Next guy up."

The Jets signed Johnson to a five-year, $72.5 million contract in free agency, which includes a $34 million guarantee -- the third-largest in team history. He got off to a sluggish start, surrendering a 67-yard touchdown reception in last week's loss to the Jacksonville Jaguars.