As the rest of his Broncos teammates began their final practice in preparation for Sunday’s game against Kansas City, star linebacker and team captain D.J. Williams walked quietly through the back doors of the team’s Dove Valley headquarters.

It was 11:21 a.m. Friday, only a short time after Williams was released from a detox facility where he was taken by police shortly before 3 a.m. after being arrested on suspicion of drunken driving, his second such arrest in his seven years with the Broncos.

By 11:35 a.m., Williams was back in his Hummer SUV, driving away from the facility as practice continued on without him. Coach Josh McDaniels said he was unsure if Williams would play Sunday against the Chiefs.

“The behavior, and the fact that we’re two days away from a game, it’s very disappointing to me, to our entire organization, and it would be no matter who it was,” McDaniels said.

Yet it was certainly disheartening news too, because Williams is a team captain, and as the leader in both tackles (57 solo) and sacks (3.5), he has arguably been the defense’s best player through the first half of the season.

Williams, who earlier Thursday night attended the Nuggets-Lakers game at the Pepsi Center, was pulled over at 2:40 a.m. in the 900 block of South Broadway, south of downtown, because the headlights on his Hummer were not on. An NFL source said Williams refused to take a Breathalyzer test at the scene, and he was taken to a DUI facility overnight. Williams’ first court date has been set for Dec. 13, the morning after the Broncos’ game at Arizona.

But Friday’s arrest puts Williams’ immediate availability for the Broncos into question, as well.

It would not be a surprise if the Broncos followed the precedent set this season by the New York Jets and Tennessee Titans, who benched their star receivers Braylon Edwards and Kenny Britt, respectively, for one quarter following similar incidents.

Williams also faces a possible multigame suspension from the league for a second violation of the league’s substance-abuse policy. He was previously charged with DUI in 2005, though he pleaded guilty to a lesser charge of driving while impaired.

“Yeah, it’s embarrassing,” Williams told The Denver Post in 2005. “I know now you’ve got to have a driver or somebody driving you around when you plan on going out like that.”

McDaniels could choose to enforce his own punishment before NFL commissioner Roger Goodell makes his ruling. McDaniels routinely preaches the importance of character, and has previously suspended players (Brandon Marshall and Tony Scheffler for the final game of 2009, as example) for disciplinary matters not involving the legal system.

“This is going to involve more people than just us,” McDaniels said. “But we’re going to certainly do what’s in the best interest of our organization.”

Williams also faces potentially severe legal consequences. Under Colorado law, if convicted of a second alcohol-related offense, Williams would receive a mandatory jail sentence of at least 10 days, which at the discretion of a judge could be served at home, and a minimum of two years’ probation.

Williams was not available for comment Friday. Several defensive teammates also declined to talk about Williams’ arrest.

The Broncos linebacker corps is already thin. Williams’ backups inside are Wesley Woodyard, who has missed five games this season with injuries, and Joe Mays, who has only two career starts. The Broncos’ other inside linebacker, Mario Haggan, has been playing outside while Robert Ayers is out with a foot injury — though Haggan likely could move back inside and handle the linebacker calls that Williams normally makes, giving Jarvis Moss more playing time outside.

Denver Post staff writer Mike Klis contributed to this report.

Lindsay H. Jones: 303-954-1262 or ljones@denverpost.com, www.twitter.com/postbroncos or @PostBroncos