Novak Djokovic and Milos Raonic headline the Rogers Cup in Toronto

Top-ranked Novak Djokovic and Wimbledon finalist Milos Raonic are part of a star-studded line-up at the Rogers Cup in Toronto as the hard-court swing begins in earnest ahead of the Rio Olympics and the US Open.

Live ATP Masters Tennis

The Masters event will be seen as a warm-up for the Olympic games which runs from August 6-14. Players not taking part in Rio will then prepare for the final major of the year at the Western & Southern Open in Cincinnati, live on Sky Sports, before heading to Flushing Meadows for the US Open starting on Monday, August 29.

Former champions Roger Federer and Rafa Nadal have pulled out, leaving the tournament without three of the world's top four players.

The decision by Swiss world No 3 Federer and Spanish world No 4 Nadal comes a day after Wimbledon winner Andy Murray, ranked second, said he would not defend his title so he can rest before defending his Olympic singles crown in Rio.

Federer, a 17-times Grand Slam champion who won the Canadian stop in 2004 and 2006, said he needed more time off after his bid for a record-extending 18th major title ended in the Wimbledon semi-finals earlier this month.

"Looking ahead, it is best for me that I take more time after Wimbledon," the 34-year-old Federer, who will seek his third Olympic medal at next month's Rio Games, said. "I look forward to coming back to Canada next year."

Nadal, who has been out of action since pulling out of the French Open following his second-round match with a wrist injury, said he was not fit enough to return to competition.

The 30-year-old Spaniard, a three-time winner of the tournament that alternates each year between Toronto and Montreal, was only recently given clearance to compete in Rio despite not fulfilling the qualification criteria.

"I only started practicing a week ago after my wrist injury and I am not ready to play such an important event," said Nadal.

Murray is coming off his second career Wimbledon victory, beating Canada's Raonic in three sets in the final to land his third major crown.

"I always look forward to coming to Canada and it's the first time I've missed the tournament, the guys there do a great job and always look after the players," said Murray, a three-time Rogers Cup champion.

"My body needs some recovery time after reaching the latter stages of tournaments over the past few months. I'm sorry to my fans in Toronto, but I look forward to being back in Canada next year."

There are still a whole host of top names to look out for in Canada with the likes of Stan Wawrinka, Kei Nishikori, Dominic Thiem, Tomas Berdych, Marin Cilic and Gael Monfils all taking part.

Don't miss the action which gets underway on Monday on Sky Sports 3 HD, your home of Tennis, from 4pm.

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