While this put Djokovic on the right path towards his bid for his first Olympic gold, the 37-year-old questioned why he faced a player who had not played a top-level singles match for two years.

"There were a lot of singles players that had plenty of time, there were alternates, that could have been told to come," Djokovic told reporters.

"So this part I don't get and I really hope that the (tennis governing body) ITF along with the Olympics will consider changing this rule because it's tough on Matthew. He told me it's been over two years [since] he played an official singles match and he said this was his last singles match, he's officially retired. So as I said, it's not a great feeling for him being on the court like that.”

Three-time Grand Slam doubles champion Ebden, who will be a medal contender in Paris with partner John Peers, was only placed in the singles draw after many of the leading singles players pulled out due to illness or injury, including world number one Jannik Sinner who withdrew last minute due to severe tonsillitis. 

International Tennis Federation spokeswoman Heather Bowler said the group devises the Olympic rules for the sport in conjunction with the International Olympic Committee. The cutoff for having an athlete on an Olympic roster for tennis is a week before the opening ceremony, later than most other sports in the Games. However, with top seeds all pulling out of the singles, the options for replacements were limited to doubles specialists already in Paris.

"We'd love to have last-minute replacements, but in the grand scheme of things, with 10,500 athletes and 206 National Olympic Committees (at the Games), it's logistically extremely difficult and there has to be a cutoff point for off-site replacement at some point," Bowler told ESPN.

Carlos Alcaraz, who also faced an easy opener against Lebanese alternate 275th-ranked Hady Habib, was also left questioning why Ebden was playing singles. The Spanish second seed defeated Habib 6-3, 6-1 in the first round.

"I think it should be different, because if the next single player decides to be here, if someone withdraws from the tournament, the rules are the rules, we have to follow it," the 21-year-old French Open and Wimbledon champion said.

Tennis begins at 12:00 CEST on Roland-Garros' Philippe-Chatrier court with the men's and women’s singles.