Stewards at Forest Green ejected a Grimsby Town fan from the ground before kick off - apparently for playing with an inflatable football.
Several people - including at least six stewards were seen to physically eject the man from the ground, and one appeared to have him in a headlock.
One fan told the Grimbsy Telegraph that the move had angered supporters.
In a statement, FGR said: "Forest Green Rovers are investigating an incident before the kick-off to yesterday's game against Grimsby Town at The New Lawn, where a fan was removed from the away end of the ground.
"FGR accepts the photos of the incident do not make good viewing for a club that prides itself on being family-friendly and welcoming to away fans.
"The club are awaiting the post-match report from the stewarding company before we comment further on the incident."
