Gay was not flagged on the play, and the ensuing fumble he caused led to a touchdown pass from Ben Roethlisberger to Emmanuel Sanders. The fine was issued after the Steelers had lost to the Baltimore Ravens Thursday night.
Steelers coach Mike Tomlin may be picking up a fine of his own after he found himself on the field during a kick return by Baltimore's Jacoby Jones. The NFL is reportedly investigating the matter.
Pittsburgh defeated Cleveland, and a win over Baltimore would have put them in the driver's seat for the AFC's final wild card spot, all in Pittsburgh's bid to become the first time since the 1992 Chargers - and only the second team in league history - to qualify for the postseason after starting 0-4.
At 5-7, there is no margin to give, and they will need to win out as well as receiving help in the form of other teams' losing if they are to make the playoffs.
More from Behind the Steel Curtain:
- Steelers drop close one to Ravens: All postgame news and updates following Baltimore's 22-20 win over Pittsburgh
- Harbaugh jokes but accepts Tomlin's mistake as part of the game
- Hit on Bell broke part of his helmet
- Report: League investigating Tomlin, and could issue fine for stepping on the field
- Lawrence Timmons, Ben Roethlisberger top PFF grades vs. Ravens
- Ben Roethlisberger ties Terry Bradshaw's career touchdown passes mark
- Jacoby Jones is decidedly not Usain Bolt