Coach Matt Eberflus announced Friday that defensive coordinator Alan Williams will miss Sunday's game at Tampa Bay for personal reasons.

Eberflus also told reporters he will fill in as the Bears' defensive coordinator against the Buccaneers. Eberflus said there is not a time frame on Williams' return.

"Alan Williams will not travel with the team this weekend," Eberflus told reporters during Friday's press conference. "He's out for personal reasons. I will be assuming his responsibilities."

Prior to taking the Bears' head coaching job last season, Eberflus served as Colts defensive coordinator for four seasons.

"I've done it for 12 years total," Eberflus said regarding the playcalling. "It's really more about the operation of the game management side of it. When the offense is up, it'll be normal business and then throwing challenge flags, being right there with Luke [Getsy] and the offense. When the defense is up, I'll be giving the calls. And then when we're off the field, to make corrections pretty quick, guys on the sideline are going to help me do that with the players. Really from there, it's about setting up the next series – what's coming the next series – for those guys and communicating that."

With Eberflus handling both the head coach and defensive coordinator duties Sunday, he will lean on his assistant coaches to help balance the workload.

"I would say that we've got a lot of experience on the defensive staff," Eberflus said. "Jon Hoke is a very experienced coach. Andre Curtis, very experienced coach. They've been in the league a long time, they've been in our system a long time. [Dave] Borgonzi has been with me a long time. [David[ Overstreet, all those guys have been with me so they know how I like to operate, they know how it is when I am calling the play and running that side. So it'll be good."

Eberflus also said the team has handled the situation well, noting that "the practices have been good" with "high energy."

Safety Jaquan Brisker told reporters Friday afternoon that "it's just a good challenge this weekend with coach Flus calling the plays." The second-year pro added the defense is prepared for the shift in playcallers.

"Nothing changes at all," Brisker said. "Everybody's just doing their job. We play all as one and coach Flus [has] been calling plays for a long time; this is his defense. So it's going to be a smooth process.

"We all feel good. We all feel comfortable so we're ready to go."