John Sifford Denney (born December 13, 1978) is an American football long snapper who is currently a free agent.
He played college football for Brigham Young University (BYU), and was signed by the Miami Dolphins as an undrafted free agent in 2005.
As of the 2018 season, he is the longest tenured player on the Dolphins roster, having been with the team since 2005, the same year they nearly signed quarterback Drew Brees and when they were coached by Nick Saban.
He is second in Dolphins history in games played, behind only Pro Football Hall of Famer Dan Marino.