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For the last game of the 1975 season, DB Joe Beauchamp was a Cleveland Brown
There is no record of him actually appearing in a game for the Browns.
He was acquired before the last game of the season. He did not play. It is not clear to me if he was actually active for the game; he isn't listed on the gamebook as a DNP. But either way, he "was a Cleveland Brown" for that game, whether he played or not.