Raonic, Nishikori, Gulbis and Dimitrov among a rising tide on Big Four shores

Milos Raonic is, if not quite anonymous, then certainly nothing approaching a household name in the mind of the general public.

The 23-year-old Canadian has only five minor ATP titles to his name in the last three years and only started making deeper runs at the grand slams this year, reaching the French Open quarter-finals and then the Wimbledon semis.

So when he comes out saying stuff like, ”There’s a lot of people hungry in this sport. It’s unfortunate to see him go but there are too many ... licking their chops,” in reference to Rafael Nadal, as he did at the Washington Open on Wednesday, there’s at least a tinge of presumptuousness to it.

Nonetheless, Raonic is the seventh-ranked player in the world, part of a mostly imperceptible rising tide – for now – along the still-impenetrable shores of the Big Four. And he’s not wrong – Nadal is indeed vulnerable, and he’s not the only one.

While Novak Djokovic looks back on the rise, the rest of his brethren at the top of tennis appear increasingly assailable.

His victory at the French Open victory masks an otherwise spotty season for Nadal. First fitness issues probably cost him the Australian Open to Stan Wawrinka. Then he was beaten on clay in both Monte Carlo (by David Ferrer) and Barcelona (by Nicolas Almagro) in the run up to Roland Garros, and was on the ropes in Madrid until Kei Nishikori had to retire.

Now Nadal, coming off a fourth-round Wimbledon loss to Aussie teenager Nick Kyrgios, is injured again ahead of the US Open, with a wrist ailment expected to keep him out of both the Toronto and Cincinnati Masters tournaments.

And if it's still a little premature to say Andy Murray has peaked and Roger Federer is past the point of no return, then it's only a little bit so.

Meanwhile, Raonic and his pack of “hungry” challengers are gaining ground by the tournament. There are four (five if you count the perpetually injured Juan Martin del Potro) players in the top 15 of the ATP rankings aged 25 or younger – Raonic (No 7), Grigor Dimitrov (9), Nishikori (11) and Ernests Gulbis (13), and between them this year they’ve had a few close calls with the Big Four and even taken a few back their way.

Djokovic, the undisputed top dog of the moment himself, needed two tie-breaks in a four-set win over Dimitrov in the Wimbledon semis, four sets to finish off Gulbis in the French Open semis and two tie-breaks to beat Raonic in the semis at Rome. Nadal lost the first set to Raonic in the Miami quarters before recovering and twice needed a pair of tie-breaks to beat Nishikori (round of 16) and then Dimitrov (quarters) at the Australian Open.

He also, of course, lost to Kyrgios, and was felled by 25-year-old Alexandr Dolgopolov (now world No 17) in the Indian Wells round of 32.

Federer lost to Gulbis in a memorable round of 16 match at Roland Garros and lost to Nishikori in the Miami quarters. And Murray has been beaten by Dimitrov twice this year – in the Wimbledon quarters and Acapulco semis – and lost to Raonic in the Indian Wells round of 16.

That’s not to say the ground has totally shifted yet – the Big Four have won most of their meetings with the Precocious Quartet and, as just one point of example, Federer notched a dominant victory over an erratic Raonic at the Wimbledon semi-finals.

But the levee is looking leaky.

It’s not that Murray, 27, Djokovic, 27, Nadal, 28, or even Federer, 32 (well, maybe Federer) are old. It’s just that the gap they enjoyed with more contemporary challengers like Wawrinka, Ferrer, Tomas Berdych and Jo-Wilfried Tsonga, among others, looks smaller with the currently maturing set.

There's no need to pronounce the death of the Big Four. But if you're looking for their eventual successors, there's a decent chance you'll be able to catch them giving a Nadal or Federer fits in Flushing Meadows in a few weeks.

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