Shingo Kunieda, the most successful men's wheelchair tennis player of all time, has announced his retirement.

He retires as the world's top-ranked player, having won the singles titles at the Australian and French Opens and Wimbledon last year.

"I felt I have done enough with what I want to accomplish," he said.

Kunieda won 11 singles titles at the Australian Open in addition to eight victories at the French Open and eight at the US Open.

He completed the career 'Golden Slam' - where a player wins all four major titles and the Paralympic gold medal - with his victory at Wimbledon last year.

He also won 22 Grand Slam doubles titles.

"I've been thinking about retirement since my dream came true at Tokyo Paralympics," he said.

"The Wimbledon singles title made me feel that my energy was little left to compete."

The Australian Open wheelchair tournament begins on Tuesday with Britain's Alfie Hewett now top seed and world number one.

BBC Sport's Elizabeth Hudson

Since first picking up a tennis racket aged 11, two years after being diagnosed with a spinal tumour, Kunieda has gone on to become one of the true greats of the sport.

As well as his 117 career singles and 83 doubles titles, he spent an amazing 582 weeks as men's wheelchair tennis world number one - Novak Djokovic, who holds the men's record, has had 373 weeks in top spot.

After elbow surgery, he returned to the sport, winning an emotional third Paralympic singles gold at his home Games in Tokyo in 2021, after delivering the athletes' oath at the opening ceremony.

But Kunieda also leaves Japanese wheelchair tennis in a strong position, with four players now in the top 12 in the rankings.

The brightest star of all is surely 16-year-old Tokito Oda, now world number three, who looks set to take over his mentor's mantle as world number one sooner rather than later.