Three-time Wimbledon champion John McEnroe has admitted unwittingly taking steroids for six years.
Reacting to Greg Rusedski's admission that he had tested positive for banned steroid nandrolone, McEnroe admitted he had been unaware he was being given a form of steroid for six years.
"I'm not sure some of the legal prescriptions, some of the strong, anti-inflammatory drugs people are given for speeding up the healing process, are that far removed from illegal ones," McEnroe told the Sunday Telegraph.
"For six years I was unaware I was being given a form of steroid of the legal kind they used to give horses until they decided it was too strong even for horses.
"So people have to become more aware of what they are putting into their bodies. In general people are administered drugs too readily."
McEnroe was the world number one from 1981 to 1984 and won the US Open four times.