Mike Vrabel joined the Patriots as head coach in a throwback to the Bill Belichick era. But his tenure won't involve Belichick's son, Brian.

Vrabel hired McMillan in 2021 as a defensive assistant where he primarily worked with Titans outside linebackers. In 2022, he worked as a defensive line assistant coach alongside Williams, who was named the Patriots defensive coordinator. McMillan continued to work with Titans defensive lineman in 2023.

Vrabel has a mix of experience and youth on his Patriots coaching staff, including Doug Marrone, Thomas Brown and Ashton Grant on offense.