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.

Mike Vrabel continues shaping his New England Patriots coaching staff, bringing in a former Tennessee Titans ally to strengthen the defense. The New England Patriots have welcomed Mike Vrabel back to the organization,

With Mike Vrabel having spent a season with the Cleveland Browns, there was always going to be a risk he would poach an assistant or two at his next head coaching job.