The cancellation of Wimbledon because of the coronavirus pandemic, and the uncertainty around the rest of the tennis season, could put an end to the Grand Slam title chase for Roger Federer and Serena Williams.
This week, Wimbledon was called off for the first time since World War II, and professional tennis was suspended until July 13.
However, tennis administrators have suggested the shutdown could extend to the end of the year. Tennis Australia head Craig Tiley and All England Lawn Tennis Club CEO Richard Lewis both said the sport might be done for the year.
The tennis suspension will have a financial impact on many lower-tier players who may face a long period without income.
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But for Federer and Williams, two of the greatest to ever play the sport, it will be their legacies that may take a hit, as both players face a possible end to their historic Grand Slam chases.
The 38-year-old Federer last won a major title at the 2018 Australian Open and came close to adding to his 20 Grand Slams in last year's Wimbledon final.
His next opportunity would be the US Open, which is scheduled to start on August 31, if further suspensions don't occur.
Australian Todd Woodbridge, who won the Wimbledon doubles nine times, said he was unsure what lay ahead for Federer if the rest of the season was lost.
"The question that Roger will have to ask himself is how motivated is he to come back for another year?" Woodbridge told AAP.
"Or has this actually helped him? But the less match play that you get in this period at that age, it's so much harder to come back and recover once you start again.
"It has stopped the potential ... of Federer winning one or two more. It becomes very highly unlikely for him."
Federer, who said he was "devastated" Wimbledon was cancelled, has suggested he would return for next year's event.
Williams, on the other hand, has been quieter about her future in the sport.
The 38-year-old American lost in last year's Wimbledon final and is still one Grand Slam short of tying Margaret Court's record of 24. She hasn't won a Grand Slam since giving birth to her daughter in 2017, despite reaching four finals.
Fellow tennis great Martina Navratilova says the clock is ticking for both Federer and Williams.
"The youngsters are missing a chance to improve and match up against higher-ranked players," she told Reuters. "The middle players are kind of stuck, and the older players like Serena Williams and Roger Federer, time is not their friend.
"So they lost basically this year this opportunity."