A stone-faced Rusedski, accompanied by his lawyers and wife Lucy, arrived by limousine in the morning for the hearing into his positive test for the banned steroid nandrolone.
He strode purposefully into an office building without acknowledging the media.
Eight hours later, the big-serving British number two sneaked out of a back entrance, avoiding a large media contingent and speeding off behind tinted windows.
In between, however, Rusedski, who was born and raised in Montreal, likely had plenty to tell a three-man panel appointed by the Association of Tennis Professionals (ATP) to investigate drugs test he failed last July.
Rusedski has denied taking performance-enhancing drugs.
The tribunal, headed by prominent Montreal lawyer and former UN ambassador Yves Fortier, is expected to take up to two weeks before rendering a decision.
If found guilty, the 30-year-old Rusedski could face a ban of up to two years, effectively ending his career.
Midway through the marathon session, Fortier's executive assistant Micheline Corriveau told journalists none of the parties involved in the hearing would make a comment on the day's proceedings.
The strain of the long day was evident as Rusedski's wife snapped at reporters as she and her husband, the 1997 U.S. Open finalist, sped away.
It is believed Rusedski's defense is centred around the fact that seven other players on the men's professional tour were exonerated after an independent inquiry ruled last year that they had taken contaminated electrolite supplements handed out by ATP trainers.
The ATP, who run the men's tour, stopped its staff handing out the supplements in May 2003.
Rusedski tested positive for nandrolone two months later and is believed to be the only player to have exceeded the allowable limit since the announcement.
Representatives from the World Anti-Doping Agency (WADA), which is conducting its own inquiry into those seven positive tests, had expected to sit in on the hearing.
However, in a late change of heart, Rusedski barred WADA, whose offices are located just blocks away, from attending.