Djokovic, who hasn’t won a Grand Slam title in two years, was far from his best against Learner Tien in the opening round at Flushing Meadows.Novak Djokovic delivered a lesson in Grand Slam tenacity to Learner Tien in the first round of the US Open, as he battled past the American teenager 6-1, 7-6(3), 6-2 and launched his latest quest for a record 25th major title.Competing in his first singles match since reaching the Wimbledon semifinals last month, and swapping the whites for a sleek all-black outfit, the 38-year-old Serb fought through physical issues on Sunday to secure his 80th win at Arthur Ashe Stadium.Victory also meant Djokovic became the first player since the sport turned professional in 1968 to win 75 straight opening-round matches at the Grand Slams, with 55 of those wins coming in straight sets.“It was a strange kind of match,” said Djokovic, who looked to be struggling with an injury midway through the match.“The first set was 20 minutes, and then the second one was one hour and 20, quite the opposite sets we played. It was key for me to hold my nerve in the second set and clinch it in a tie-break.“After that, I started feeling better. I can always do better, but it’s a great way to start this year’s c …
