Boston Celtics coach Joe Mazzulla has shown up at New England Patriots practices in the past. So he extended an open invitation to newly-hired Patriots head coach Mike Vrabel to do the same at the Celtics’ practice on Saturday. Vrabel reportedly accepted and showed up at the practice.

Mike Vrabel has put together a quality staff as the Patriots head coach, but it might have been a bad move not to retain CBs coach Mike Pellegrino.

The Celtics had two head coaches present at Saturday morning’s practice. One, of course, was Joe Mazzulla. The other: Mazzulla’s new Patriots counterpart, Mike Vrabel.