Two-time grand slam finalist Kevin Anderson has announced his retirement from professional tennis aged 35.

The 2.03m tall South African was the runner-up to Rafael Nadal at the US Open in 2017 — No. 32 at the time, Anderson was the lowest-ranked finalist in tournament history — and to Novak Djokovic at Wimbledon in 2018.

Anderson won seven ATP Tour singles titles, most recently at the Hall of Fame Tennis Championships in Newport, Rhode Island, last July. All of his trophies came on the speedier surfaces of grass or hard courts, which helped add oomph to his booming serves.

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“Tennis carried me far beyond my roots in Johannesburg, South Africa, and truly gave me the world,” Anderson wrote on Twitter in posts about what he called a “difficult decision to retire.”

“I’ve experienced so many different challenges and emotions; this sport can be exhilarating and at the same time lonely,” he said.

As a kid, my dad used to tell me that success isn’t defined by results, but by the effort and sacrifice you make along the way in becoming the best you can be. I gave it my best.”

Anderson reached a career-high ranking of No 5 in 2018, after his run to the final at the All England Club.

That included a 13-11 fifth-set victory over 20-time Grand Slam champion Roger Federer in the quarter-finals after facing a match point, and a 26-24 fifth-set victory over John Isner in the semi-finals, before the loss to 20-time Grand Slam champion Djokovic.

That match against Isner served as the tipping point for Wimbledon to use tie-breakers for the final set . All four announced this year they now will play tie-breaks at six-all in the deciding set.

Anderson subsequently slid out of the top 100 following a succession of knee, shoulder, ankle and elbow injuries and is currently ranked 107. He last competed in the Miami Open in March.

Anderson has been an advocate for reducing plastic use on the tennis tours and his charitable efforts earned him the 2019 Arthur Ashe Humanitarian Award.