NEW YORK: In June, Rafael Nadal spoke of a new dawn in tennis, the end of a golden era dominated by himself, Roger Federer, Novak Djokovic and Andy Murray.

On Monday, Nadal's fears were realised in the imposing 6ft 6in (1.98m), 180lbs (82kg) figure of 25-year-old Marin Cilic who swept aside Kei Nishikori to win a maiden Grand Slam title at the US Open in his 28th major. Cilic and Nishikori contested the first Grand Slam final not to feature either Djokovic, Federer or Nadal since Australia in 2005, when Marat Safin was beating Lleyton Hewitt.

It was the days before Twitter.

His win also follows Stan Wawrinka's maiden Grand Slam title at the Australian Open in January which marked the first time a man outside the big four had won a major since Juan Martin del Potro clinched his first Slam at the 2009 US Open.

Nadal was speaking from a position of strength when he looked into his crystal ball and saw only clouds -- he had just wrapped up a record ninth French Open.

And Cilic sees cracks beginning to appear.

“A lot of guys are saying people would like to watch the top four guys much more to extend their run at the Grand Slams because they attract the fans and the TV,” said Cilic.

“But one day definitely they gonna go out and there's gonna be a need for somebody else. I feel this year the guys from the second line were a bit lucky because Andy was having trouble with his back; Wawrinka was up and down after Australia; few other players were not playing at the best all the time.

“And Rafa is not here. So that opened a little bit the gate for everybody else. I feel it's gonna definitely be much bigger competition from next year.

“I feel the guys at the top are gonna pull the other guys, too. I think the game of tennis is definitely going to evolve much more. “The raw statistics suggest that Djokovic, Nadal, Federer and Murray are not the powers they once were.

World number one Djokovic claimed a second Wimbledon title this year and seventh Grand Slam in total, but was runner-up at the French Open, a semi-finalist in New York and a quarter-finalist in Australia.

Power cuts

The Serb, seemingly distracted by impending fatherhood, has four titles to his name in 2014; in 2013, he won seven.

Nadal was runner-up to Wawrinka in Australia, champion in Paris but was knocked out in the fourth round at Wimbledon.

The 28-year-old hasn't played since, forced to skip his US Open defence with a wrist injury, the latest setback in a long history of physical problems, mostly concerning his fragile knees.

Nadal's title count for 2014 has stalled at four after claiming 10 in 2013.

Federer, who was hoping to be the oldest Grand Slam champion in more than 40 years by winning in New York, was swept away in straight sets in the semi-finals by Cilic, eight years his junior.

In July he was runner-up at Wimbledon, where he won the 17th and most recent of his majors in 2012, was a semi-finalist in Australia but was a fourth round loser in Paris, his earliest exit at Roland Garros in a decade. Meanwhile, Murray is still without a title since his 2013 Wimbledon triumph.

He was a semi-finalist in Paris but was beaten in the quarter-finals in Australia, Wimbledon and New York. The Scot is on the verge of slipping out of the world top 10 for the first time since 2008.

The stars bristle at suggestions that their powers may be on the slide.

“You create your stories,” snapped Federer after his New York defeat.

“You said the same in Australia and then we know what happened at the French Open final, Wimbledon final.

“Nishikori, the first Asian man to play in a Grand Slam final, defeated three of the top five seeds to make the championship match -- Raonic, Wawrinka and Djokovic.

He too believes that he as well as Raonic and Grigor Dimitrov -- both Wimbledon semi-finalists and members of the top 10 -- are within touching distance.

“A lot of young guys are coming up. Dimitrov, Raonic did semis in Wimbledon. I think it's great for the tennis. For me, I'm not that young anymore, so I put my pressure on myself to do well,” said the 25-year-old.

“For sure there's going to be a lot of changes. Cilic and Del Potro (currently injured) is not here, but he's still a top player. I hope I see more changes.”