Nishikori to face Djokovic ; Sock Returns to Slam Form; Hurkacz Out to Seppi - US Open Day 4

US Open Day 4 is complete: 1) Kei Nishikori edges past Mackenzie McDonald in five sets, renewing his rivalry with Novak Djokovic for the 20th time in round 3; 2) Jack Sock makes it to round 3 of a Grand Slam for the first time since 2018; 3) Andreas Seppi finds form in his late-career, upsetting 10th-seed and streaking hard-court player Hubert Hurkacz... ...and more news from US Open Day 4! Stay tuned. If you're enjo