Federer, 36, downed Marin Cilic in a five-set thriller to win his 20th Grand Slam title.

But victory has been overshadowed by the circling of retirement rumours following the win.

Federer, speaking on court after winning the title, said: "You guys, you feel the stadiums, you make me nervous. You make me go out and practise.

"I'd just like to thank you for everything, It wouldn't be the same without you, thank you.

"Marin's team as well. You guys work hard, all the best."

He then shook his head and put his tongue out as the emotional overspilt.

"And my team, I love you guys. Thank you," he added - before the tears flowed.

Eagle-eyed fans have noticed Federer didn't say he would see the supporters next year and they think that's a sign the Swiss is on his way out.

They took to Twitter in their droves to suggest the theory with one writing: "Is Roger Federer going to retire? No mention of his customary "see you next year" and strangely emotional about winning considering how calm he was last year after beating his worst nightmare. Think 2018 could be the last year in a legendary career for @rogerfederer #AusOpen."

Another agreed and said: "CONSPIRACY THEORY: Federer is crying because his going to retire at the end of the year and he hasn't said anything to anyone else yet. That's why this win means a lot to him because it will be his last ever #AusOpen and his happy he won for the last time."

While a fellow fan wrote: "No "see you next year" from Federer. Don't want to read too much into it, but I dread the day he retires. Never retire, please. #AusOpen."

That same point was made by another Twitter user who said: "Federer is so emotional in his victory speech despite it being a pretty easy tournament for him. I wonder if it's his last year and will retire next year."

"I have a feeling that part of the reason Federer is so emotional is that secretly he wants to retire but he cannot bring himself to do that while he is still competing well in the biggest events.... Not really but why is he crying more this time!?" another added.

Federer has now won 96 titles in his stellar career. The elated champion said: "I'm so happy. It's unbelievable.

"It's been a long day waiting for the finals. It's easier in the afternoon time, you sleep, go out there, play and do your best but when it's at night you think about the amtch all day and it's tough.

"I'm happy it's over now either way.

"Winning is a dream come true. The fairytale continues for us, for me, and after the great year I had last year it's incredible.

"I'd like to thank Marin, another great tournament, congratulations for the world No 3 as that's a great achievement and I wish you all the best.

"Keep doing what you're doing and you can achieve more."

FEDERER'S GRAND SLAM VICTORIES

Australian Open - six titles (2004, 2006, 2007, 2010, 2017, 2018)

By reaching his seventh final at Melbourne Park, Federer set a new Open era record at the tournament, and his triumph saw him equal Novak Djokovic and Roy Emerson's six titles. He won his second slam title in Melbourne in 2004 with victory over Marat Safin, while last year's unexpected triumph was arguably the greatest of his career. His only final defeat came against Nadal in 2009, and he staved off Cilic's threat with a clinical final set on Sunday.

French Open - one title (2009)

Another of Federer's favourite titles came nine years ago when he finally lifted the Coupe des Mousquetaires at Roland Garros. It was Federer's fourth consecutive final and he had lost the previous three to Nadal. Robin Soderling stunned Nadal in the fourth round in 2009 and Federer defeated the Swede in the final.

Wimbledon - eight titles (2003, 2004, 2005, 2006, 2007, 2009, 2012, 2017)

When he finally retires, Wimbledon will be the grand slam most synonymous with Federer. He won his first title in 2003 against Mark Philippoussis and did not lose a match at SW17 until the extraordinary final against Nadal in 2008. After defeating Andy Roddick in a marathon in 2009 and Andy Murray in 2012, victory over Cilic last summer made Federer the first man ever to win eight titles.

US Open - five titles (2004, 2005, 2006, 2007, 2008)

It is nearly a decade since Federer won the last of his five successive titles in New York with victory over Murray in 2008. He had previously beaten Lleyton Hewitt, Andre Agassi, Andy Roddick and Novak Djokovic in his finals. Federer also made the final at Flushing Meadows in 2009 and 2015, losing to Juan Martin del Potro and Djokovic, respectively.