Here's a player who came off the bench to make a tackle...funny:
Story about play: Dickie Maegle tackle
Also a list...a coach made a tackle at#7 on the list:
ESPN.com - Page2 - The List: Coaches gone wild
7. Fairfield coach tackles opposing player
November 1978. Fairfield (Connecticut) University led Western New England College 15-14 in the third quarter. Western New England's Jim Brown, returning a kickoff, had eluded every Fairfield defender and appeared to be on his way to a touchdown. Then, Fairfield coach Ed Hall ran out and tackled Brown at midfield. "Are you out of your mind, coach?" said Brown. "I guess I am," said Hall.
Hall, then 48, had played running back and defensive back for the University of Bridgeport in his prime, about two decades earlier. Brown was credited with an 84-yard TD run. The ref tossed Hall from the game.
"Something just happened to me," said Hall, "and the next thing I knew, the referee was standing over me and screaming at me to get out of the game. As I started walking to the rear of the bleachers, with the crowd booing me, I broke down and cried."
Even weeks later, Hall couldn't explain what happened. "I've been coaching for 22 years, and there have been many instances where opposing players have run right in front of me. But I never had a strong impulse to tackle them."