Greg Rusedski will today fight to save his career after testing positive for the performance-enhancing drug nandrolone.
The British number two will appear before the Association of Tennis Professionals' (ATP) anti-doping tribunal in his home town of Montreal.
Arriving in the Canadian city, Rusedski said: "I'm very confident about the situation. I have stated all along I believe that I am innocent and hopefully the tribunal will decide on that."
Rusedski has protested his innocence since it became known last month that he had tested positive on July 23rd, last year at the RCA tournament in Indianapolis.
He has argued that his sample contains the same "unique analytical fingerprinting" as seven other players, cleared after the ATP decided they tested positive after taking supplements handed out by the governing body's own trainers.