Gregory launched his outburst in the aftermath of Saturday's Premiership match against Liverpool when Collymore was sent off for two bookable offences - the first for a horror tackle on Steve Harkness which left him with damaged knee ligaments. But the Villa manager insisted that Collymore "never gets a free-kick or much protection" and that "referees are judging him before he steps on to the pitch."
Gregory, who will be without the pounds 7m striker for the match against Manchester United in 10 days' time, urged officials to "treat him as a footballer, not as Stan Collymore".
Elleray insisted, however, there was no truth in Gregory's claims. "We are all trained to be totally objective," he said. "Given the fact we are under so much scrutiny, if there was evidence of someone being marked out for treatment by a referee, I am sure it would be spotted.
"The difficulty that referees have in dealing with high-profile players is that some people will feel, whatever a referee does, that he is being too strict or letting the player get away with murder. We get criticism both ways."
Gregory, who yesterday placed a pounds 6m price tag on the out-of-favour striker Julian Joachim, is still refusing to say whether he has taken any action against Collymore for the challenge on Harkness.
Meanwhile, Gregory looks set to be without the services of his goalkeeper Mark Bosnich at Nottingham Forest on Saturday. The Australian, who has missed the last six games, is still struggling to overcome the shoulder injury suffered at Coventry in early October.
The Huddersfield captain Barry Horne will be out of action for the next 10 weeks because of medial ligament damage to his knee. The former Wales midfielder had a scan on his right knee yesterday after picking up the injury in Saturday's Yorkshire derby win over Bradford City.Reuse content