QPR striker DJ Campbell will be out for up to eight weeks after suffering a suspected broken metatarsal.
"He had an accident on Thursday in the last kick of the training game," said QPR boss Warnock after Saturday's 1-1 draw against Blackburn.
"He might have to have an operation. We'll know on Monday."
Warnock blamed modern lightweight boots for the foot injury, adding: "I think it is these stupid boots, they're like carpet slippers."
The 29-year-old joined the club from Blackpool in the summer but has already missed a month with an illness.
He has so far made five Premier League appearances and scored his only goal in the 3-0 win at Wolves.
Warnock added that Campbell was likely to be out for at least four weeks, possibly longer if the bone requires pinning.
And returning the to theme of footwear, Warnock said: "Don't talk to me about these boots.
"You can't ban people if they prefer it, but I think they are absolutely stupid boots to wear at the level we're talking about.
"They give you no support at all, but that's football."
Warnock also expressed his anger that news of Campbell's injury, as well as the his intention to leave out Adel Taarabt and start with Jamie Mackie, had appeared on a web forum on Friday.
"I can't believe it," added Warnock. "[Name removed] puts on this website that Campbell has broken his foot, Heidar Helguson is playing and Mackie is making his debut, while Adel Taarabt is out.
"This is supposed to be a supporter. You don't want many supporters like that. "What an advantage for the opposition.
"Obviously he has got a contact, hasn't he? But if he thinks he is helping me, if he is a QPR fan, it is exactly the opposite."