London: Kei Nishikori said he no longer fears the big four of tennis because his generation of young guns are starting to chip away at their dominance.
Rafael Nadal, Novak Djokovic, Andy Murray and Roger Federer have won 38 out of the last 42 Grand Slam titles but Nishikori is part of a new wave of up-and-coming players thought to pose a risk to their monopoly.
The 24-year-old Japanese number one has the chance to measure his progress against a fellow rising star on Tuesday when he takes on Canada`s Milos Raonic for a place in a potential Wimbledon quarter-final with world number one Nadal.
Nishikori said Stanislas Wawrinka`s win at the Australian Open in January showed how the landscape is shifting.
"This year it`s little bit changing already. Stan won Australia. Also, me, I`ve been playing well. And the young guys -- Raonic, Grigor Dimitrov -- are beating top guys also sometimes," the world number 12 said.
"I love to see it changing a little bit. I don`t have fear to play those guys anymore. I used to have, maybe last year or a couple of years ago -- but not anymore.
"They`re always there for a long time. Some secret is there, for sure, what they are doing better than the other guys. We have to learn a lot of things from those top guys. But I think we are getting closer to the top four or five."
The highest-ranked Japanese man in tennis history is contesting the last 16 at Wimbledon for the first time and hopes that his exploits on the court can inspire his countrymen to take up their racquets.
If he wins, he would be the only Japanese man other than Shuzo Matsuoka at Wimbledon 1995 to reach an Open Era Grand Slam quarter-final.
"If I can do well and send some good news to Japan, it`s going to help for sure," he said.
"I hope tennis is getting big and more players are coming up, especially young guys having really tough time coming from Asia. So I hope there is more guys coming from Asia."Nishikori reached the Wimbledon fourth round after playing just four games Monday against Italian lucky loser Simon Bolelli.
Their rain-delayed match was suspended at 3-6, 6-3, 4-6, 7-6 (7/4), 3-3 in fading light on Saturday and Nishikori returned two days later to win the deciding set 6-4.
"There was a lot of stress these two days, especially Sunday. I never had something like this, playing the fifth set, take one day off, play again. It wasn`t easy," he said.
"I try to relax in my room usually. I love to go out when I have a day off. I love to sleep. So I usually I sleep for a long time."
The scheduling means the winner of his match with eighth-seeded Raonic will have just 24 hours` rest before playing again on Wednesday.
But despite the quick-fire defeat of Bolelli on Monday, 10th seed Nishikori said he would still rather wait until Tuesday to play Raonic.
"I am too tired mentally," he said.