British number two Greg Rusedski said on Tuesday he was "cautiously optimistic" about the outcome of his drugs hearing in Montreal.
Rusedski flew into London from Canada and spoke for the first time to the media since Monday's hearing in Montreal into the drugs test he failed last July.
"I'm confident and we'll just have to wait and see," Rusedski, who was accompanied by his wife Lucy, said at Heathrow airport.
"We're cautiously optimistic so we are just hoping for the best," added the 30-year-old who tested positive for the banned steroid nandrolone during a tournament in Indianapolis in July.
Rusedski, who has denied knowingly taking performance-enhancing drugs, was grilled in Montreal by a three-man panel appointed by the Association of Tennis Professionals (ATP).
If found guilty, the 1997 U.S. Open finalist faces a two-year ban which would effectively end his career.
"I have no idea when I'm going to hear the verdict. It's anywhere between three to nine days. So all I can do is sit tight at the moment," Rusedski said. "I think things went fairly but we'll have to wait and see."
Seven players on the ATP tour were exonerated after an independent inquiry ruled last year that they had taken contaminated electrolite supplements handed out by ATP trainers.
The ATP stopped its staff handing out the supplements in May 2003.