Nishikori

NEW YORK — Novak Djokovic and Roger Federer both won in straight sets in the US Open third round on Friday, but No. 7 seed Kei Nishikori became the latest men’s seed to fall at Flushing Meadows. Nishikori, a 2014 finalist at the US Open, lost to 38th-ranked Alex De Minaur 6-2, 6-4, 2-6, 6-3 …