Jason Cowley had to leave the pitch during the first half of Saturday's friendly at Halesowen.
"It's a terrible tackle, there's no two ways about it," said Hereford manager Paul Caddis.
"His ankle is the size of my thigh, his ankle is huge.
"We'll have to access it, it doesn't look good, it's nasty.
"I get frustrated, I want to play pre-season games like proper games.
"I've had a discussion with the referee, it's 100% a red card.
"He's admitted there were loads of yellow cards in the game so just do it properly.
"I didn't like the tackle, but the worrying thing is that the referee didn't see it."