The biggest injury news from the Indianapolis Colts‘ preseason opener was that quarterback Anthony Richardson was back after his “freak” eye injury last year. The second-biggest injury news was what happened to one of their coaches.

Brian Mason, the Colts‘ special teams coordinator, was part of a sideline collision on the final play of his team’s matchup against the New England Patriots. Mason was watching Colts quarterback Riley Leonard’s last-second Hail Mary attempt when two players – one Colt and one Patriot – ran into the coach.

The collision, which was caught on broadcast cameras, knocked Mason onto the ground. He could be seen screaming and rolling around for a moment before members of the Colts’ training staff came over to help him.

Note: The following video may be graphic for some viewers.

After the game, which ended in a 13-13 tie, Colts head coach Shane Steichen told reporters that Mason sustained a knee injury.

“He got rolled up right on the sideline on that last play, so we’ll see,” Steichen said.

The IndyStar reported Friday that Mason tore multiple knee ligaments. No other details were available.

The Colts did not immediately respond to USA TODAY Sports’ request for comment.