There are fears that Roger Federer’s legendary career is coming to a close, after the Swiss maestro withdrew from the Madrid Open with a back injury.

The 17-time grand slam winner announced he would pull out of the tournament – a warm up for the French Open – due to the persistent injury that first began to trouble him in 2013.

This week, Federer revealed he had aggravated his back at training, forcing him to cancel practice sessions and withdraw from the crucial Spanish tournament.

Madrid was the fifth tournament he had withdrawn from in 2016.

• From chumps to champs: Adelaide United’s amazing turnaround
• The 127kg Aussie who is ‘talk of the town’ in the US
• Former Socceroos captain declared bankrupt

It prompted speculation that the father of four, who is married to former women’s player Mirka Vavrinec, could be poised to call it quits on his dazzling 18-year career. 

Roger Federer says he’s been disappointed with his season so far. Photo: Getty

ESPN tennis expert Peter Bodo said the injury had caused a “scary feeling” in the sporting world about the future of the tennis great.

In 2013, the problem was responsible for Federer’s disastrous season, disastrous by his standards at least.

His ATP ranking plummeted to seventh in the world in that year and his run of 36 consecutive grand slam quarter-finals came to an end. He won only one tournament that year – his worst result since he broke onto the ATP scene.

In 2014 and 2015 Federer bounced back to play brilliant tennis, despite losing three times to Novak Djokovic in finals.

On Tuesday, Federer, 34, reluctantly admitted he had endured a “tough” 2016.

“I hope it gets better from here,’’ he said.

“I would rather play it safe and rest up now and get ready for Rome [Rome Masters]. I’m sorry to the tournament for coming and leaving without playing.

“I arrived and I was okay and then I practised on Saturday and hurt my back a little bit and stopped early. I’m very disappointed to say the least.”

Federer said he was not worried about his preparations for the French Open, which begins on May 22.

The last time Federer missed a grand slam was the 1999 US Open. Since then he has played 65 grand slams in a row.

ESPN tennis expert Peter Bodo wrote about the “ominous” and “eerie” feeling the tennis world felt upon hearing of Federer’s withdrawal.

“Both players [Federer and the also-injured Serena Williams] have repeatedly said they have no plans to retire any time soon,” Bodo wrote.

“But the bodies of the players might be telling them otherwise.

“It’s a scary idea [tennis without Federer and Williams]. Scary for fans, for television networks and sponsors, for everyone in tennis.”

Federer said he no longer needed a meticulous preparation and many lead-up matches before a grand slam.

“With my experience and the way I feel about big tournaments, if I have matches, great,” Federer said.

“If I don’t, I trust in my game, in my mind that I’ll be fine regardless of the preparations.”

But already in 2016 Federer’s problems have started to mount. Along with his back injury he has battled a flu, a stomach virus and knee surgery caused by a freak bathtub accident.

– with AAP