It’s hard to imagine now but there was a time before Bill Belichick was head coach of the New England Patriots. Here’s a piece of evidence in the form of a ticket stub from a game the Pats played on September 15, 1996 against the Arizona Cardinals (the program can be found here).
The front of the ticket shows New England great Bruce Armstrong blocking who I believe is Bruce Smith. In the game the Pats dominated the Cards, 31-0.