The Patriots signed Mathis from the practice squad to the active roster Tuesday.
Mathis began the regular season on the Patriots' practice squad and, after being elevated three times, he will continue to play in New England while on the 53-man active roster. The 2023 sixth-round pick has played 43 snaps (four on defense, 39 on special teams) across his three regular-season outings and has registered one solo tackle over that span.