Express sport keeps you up to date with all the latest news and scores that the US open. day four of the US Open is already upon us and the two defending Champions have continued their progress in New York overnight Novak jokovic was leading llo djr 64 6420 when an abdominal issue forced his compatriot to retire Coco G also sailed through beating Germany's tajan Maria 6060 but there was heartbreak for brid's Harriet Dart whole loss to Ukrainian 19 seed Marta kostuk the British no.3 aiming to reach the third round for the first time in her career was was way below her best as a series of unforced Errors signified her 76121 061 defeat in sweltering heat the 28-year-old cut a disconsolate figure afterwards the last three remaining British singles players ktie Bolter Jack Draper and Dan Evans are all in action today with play starting at 4M UK time Katie Bolter takes on Spanish World no.74 Jessica Bo's Monero in the second match Jack Draper then faces Argentine World n. 64 fundo Diaz aosta and after winning the longest match in US open history in the first round Dan Evans will then play the last match of the day against Argentine world and .36 Mariano Noone the two top seeds meanwhile janx CER and igch are also playing in the day session in the Arthur ashy Stadium