Aston Villa legend Tony Morley was angered by Saturday's pitch invasion.
Villa fans invaded the ground before and after the final whistle of their FA Cup win over West Bromwich Albion.
Morley, 60, told the Mirror: "It was quite frightening. It wasn't like it was just 50 people, there were hundreds.
"To invade the pitch you would say they are idiots if there were half a dozen. But there was well over a thousand people on the pitch at the end - it was crazy.
"It shows their passion, but show it on the terraces and not the pitch.
"The only thing I was very grateful for was no player, especially the West Brom players, got hurt. I couldn't even see the players among all the fans.
"You only need one idiot with a few drinks in him to do something and it would cause all kinds of problems.
"They're good supporters but there is a line to draw. The last couple of minutes you could sense the players just wanted it to be over."