Roger Federer has fallen outside the world's top 10 male players for the first time in nearly five years, leaving his legion of fans devastated.
The 40-year-old Swiss legend hasn't played since Wimbledon in July and is battling to get back on court following more troubles with his knee.
Federer fell two places to World No.11 in the latest ATP rankings released on Monday.
A change to the ranking structure during the Covid-19 pandemic had previously kept his position elevated despite his injury-hampered form.
But the 20-time grand slam champion has now tumbled out of the top 10.
It is just the 12th week in 19 years that Federer is outside the world's top 10.
It last occurred between November 2016 and January 2017 when he was also injured.
Novak Djokovic remains No.1 with 11,430 points and has an advantage of 1800 to second-placed Russian Daniil Medvedev.
Briton Cameron Norrie gained 11 spots to a career-high of 15th after winning his first Masters-level event in Indian Wells on Sunday.
Roger Federer in huge doubt for Australian Open
Federer may have played his last Australian Open after the tennis legend revealed last month that he's still "many months" away from returning from his latest knee surgery.
Federer said he's "in a really good place" with his recovery from knee surgery in August, however the 40-year-old revealed it's going to take a "few more months" to get back on the court - making a return at the Australian Open in January appear unlikely.
Federer, who shares the all-time men's record of 20 major titles with Rafa Nadal and Djokovic, had two knee operations in 2020 that kept him out of the tour for more than a year.
He returned to action in March this year but injured the knee again during the grass court season and said he needed more surgery in order to resume playing.
"It was a tough process to take that decision, just because I already had couple of knee surgeries last year," Federer told Jim Courier in an interview at the Laver Cup.
"I was really unhappy with how things went at Wimbledon. I was just nowhere near where I wanted to be to play at the top, top level.
"But I tried my best and at the end, at some point, too much is too much. Now I've just got to take it step by step.
"I've got to first walk again properly, run properly and then do the sidesteps and all the agility work and then eventually I've got to be back on the tennis court.
"But it's going to take me a few more months and then we'll see how things are at some point next year.
"I've got to take my time. I don't want to rush into anything at this point.
"This is also for my life. I want to make sure I can do everything I want to do later on.
"There's no rush with anything, so I'm actually in a really good place. I think the worst is behind me. I'm really happy."
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