Andy Murray and Stefanos Tsitsipas lead Del Potro tributes amid retirement concerns

Andy Murray and Stefanos Tsitsipas have led tributes to Juan Martin del Potro after the 33-year-old admitted his career may be over. The 2009 US Open champion had been sidelined with a knee injury for almost three years but finally made his return at the Argentina Open on Tuesday night. After losing his opening match, Del Potro admitted it could be the final match of his career.

Del Potro fractured his patella during the Shanghai Masters when he was No 4 in the world back in October 2018, making a successful comeback at the Delray Beach Open four months later, reachong the quarter-finals, but was once again out for another three months before enjoying a triumphant clay-court swing, making the quarters of the Rome Masters and the second week of the French Open.

Opening his grass court season at the Queens Club, the Argentine slipped on the centre court grass during his opening-round victory over Denis Shapovalov and had not played since.

The 33-year-old confirmed he would be making his long-awaited return at the Argentina Open before going onto next week's ATP 500 in Rio, but ahead of the tournament gave an emotional press conference to admit the tournaments were more of a farewell than a comeback.

And after losing the match 6-1 6-3 to compatriot Federico Delbonis in front of a packed arena full of fans chanting his name, Delpo doubled-down on his retirement hints as he admitted it may have been his last match and cast doubt over going to next week's Rio Open.

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"Today is a full stop. Now I have to take care of my knee for my life, for day-to-day life. But I am going to leave the window open in tennis because what I experienced tonight is