US Open: 'Big Four' in No Mood to Cede Power

Andy Murray and Rafael Nadal insisted on Friday that they have no intention of loosening their grip on power despite the sport's 'Big Four' slipping into the twilight of their careers.

Murray, Nadal, Novak Djokovic and Roger Federer have carved up 46 of the last 53 majors between them.

The physical cracks are starting to show -- Djokovic and Nadal have been bothered by wrist problems in recent weeks while 35-year-old Federer has shut down his 2016 season due to a knee injury.

But Murray, described by top 10 rival Kei Nishikori as 'Ironman' for his battling run to the Olympic Games gold medal in Rio, says that at 29 years old, he is using his age as a motivating factor.

"I'd imagine I'd be playing at this level for three, four more years, max," said Murray, the holder of three Grand Slam titles.

"It's not easy to do that. I hope I'm still playing like this when I'm 38 years old, but it's pretty unlikely.

"I'm actually using that as a positive that you have to make the most of every opportunity. It's a slightly different mentality to maybe when you're younger and like you feel like you have a bit more time on your side.

"I want to make the most of every tournament I play in and try and win and achieve as much as I can the next few years."

Nadal, a year older than both Djokovic and Murray at 30, has endured a catalogue of injury woes throughout his career, mostly involving his knees and wrists.

His most recent left wrist problem forced a withdrawal midway through the French Open, kept him out of Wimbledon and prevented even practicing for two and a half months.

But the Spaniard then went on a marathon run at the Olympics where he lost in the semi-finals of the singles but won gold in the men's doubles.

"The 'Big Four' are getting older. But still Novak is No. 1, Andy No. 2," said 14-time major winner Nadal.

"I got injured, but before the injury I was third in the race (for the Tour finals) and not very far from No. 2.

"It's obvious that we will not be here forever but I think I can play to the level I had before my injury for the next three, four years."

Djokovic, with 12 majors, believes that he remains at the peak of his powers despite a shock third round loss at Wimbledon at the hands of Sam Querrey, his earliest exit at a Slam in seven years.

His win at the French Open in June allowed him to join Federer and Nadal as one of the few men to complete the career Grand Slam of all four majors.

"I'm 29 and believe that I'm at a peak of my abilities as a tennis player," said the Serb.

"I'll try to keep that peak as consistent and enduring as much as possible."