Novak Djokovic says he is treating every Grand Slam tournament like it’s his last as he prepares to make a long-awaited return to the US Open next week. 
The Serbian star, winner of a record 23 Grand Slam singles titles, is bidding to add a 24th to his collection in New York over the next fortnight, which would put him two clear of Rafael Nadal’s 22 Slam titles. 

At 36, Djokovic said on Friday he is increasingly aware that opportunities to improve his record may become harder to come by even if he is not contemplating retirement. “I don’t know how many more slams I’ll have,” Djokovic told a press conference.