The New England Patriots will indeed be without their defensive coordinator this week. As head coach Mike Vrabel confirmed on Friday, Terrell Williams will be out for the team’s upcoming matchup with the Miami Dolphins due to the undisclosed medical situation he is currently dealing with.

In Williams’ place, inside linebackers coach Zak Kuhr will serve as defensive play caller.

“Zak Kuhr will call the game defensively,” Vrabel said during a press conference at Gillette Stadium.

“I’ll help him like I always do, but I’m excited for that. I think we’ve been prepared all week for that, for the preparation, for the game planning. All the phases of first and second down, what this team wants to try to do and how we want to try to defend them, and the keys and the plan on third down or short yardage in the red zone. It was a good week of preparation.”

For Kuhr, replacing Williams is nothing new. The 37-year-old already served as a stand-in defensive coordinator in the spring, after a medical scare forced Williams to work remotely from his home in Detroit.

Kuhr originally joined the Patriots alongside Vrabel earlier this offseason. Before their reunion in New England, they already crossed paths at Ohio State and with the Tennessee Titans. Most recently, he served as a defensive assistant with the New York Giants.

Overall, as Vrabel noted on Friday, Kuhr’s experience as a coach is quite diverse.

“Going back to just having been an offensive coach, and I watched him work at Ohio State, and when we were able to get him to Tennessee, how quickly he translated that knowledge to defense, how quickly he learned defense and what an asset he was defensively for us, especially coming from some of the college game and as some of those trends started to make their way to the National Football League, some of the spread, the RPO or things like that, he really became an asset for us defensively.” Vrabel said.

“He did our red zone stuff for us in Tennessee, and then continued to grow, continued to understand what we were doing. Then, watching him work in the spring, work in front of the guys and prepare them in the spring, and through training camp until Terrell was back, that’s what I saw: I saw a lot of maturity, a lot of growth, but also a lot of knowledge.”

The Patriots’ game against the Dolphins will kick off at 1 p.m. ET on Sunday, Sept. 14, at Miami’s Hard Rock Stadium.