Kei Nishikori admitted on Tuesday that the dominance of the ‘big three’ of Rafael Nadal, Novak Djokovic and Roger Federer has left him “stuck in the quarter-finals of Grand Slams” after another last-eight exit.

Nishikori was thrashed 6-1, 6-1, 6-3 by Nadal at Roland Garros, the eighth time in his career that he has fallen in the quarter-finals of a major.

“I have got to keep trying to work, to finish in straight sets, but that means maybe I’m not good enough tennis-wise and also mental-wise,” said the 29-year-old Japanese.

“I just have to keep working. I’m always stuck in the quarter-finals in Grand Slams, and I think the next goal is to be in the semi-final or final.”

Nishikori has been in one final at the majors when he was runner-up at the 2014 US Open to Marin Cilic.

On Tuesday, he was trying to reach his fourth Slam semi-final and be the first Japanese man to achieve the feat in Paris since Jiro Satoh in 1933.

But instead he slumped to his 11th defeat in 13 meetings with Nadal and fifth in five on clay.

Seventh seed Nishikori had played back-to-back five-setters to reach his third quarter-final at Roland Garros, spending four more hours on court than Nadal.

In the third and fourth rounds, he had to come back from deficits in the final sets.

The efforts took their toll Tuesday, needing treatment on an upper right arm injury throughout the second and third sets.

Nishikori managed just nine winners in total in the first two sets.

As the skies darkened over the city, so did Nishikori’s mood as he slipped 4-1 down in the third.

Even an 80-minute delay to ride out a spectacular thunder storm didn’t help as Nadal needed just another eight minutes to finish the job.

“I wish I could finish in three sets,” said Nishikori, whose lifetime combined record against Nadal, Djokovic and Federer now stands at just seven wins against 34 defeats.

“For sure I played too many hours on the court here and Rafa didn’t let me play how I wanted to play.

“If I’m not fresh, it’s not easy to stay with him. He hit very heavy, and he was serving well. He made me play every point.

“Even to get one game, it felt like it was a very long time to get it.”

Nadal gave Nishikori words of encouragement, insisting that his presence in the world top 10 for five of the last six years is testament to his staying power.

“He’s always a very good player always. Five years ago, he played the final of the US Open.

“I feel that everybody’s dangerous. And Kei is seven in the world. So he (is) the world’s seventh most dangerous player in the world today.”