Novak Djokovic delivered a lesson in Grand Slam tenacity to Learner Tien in the first round of the US Open on Sunday, battling past the American teenager 6-1 7-6(3) 6-2 to launch his latest quest for a record 25th major title.
Competing in his first singles match since his run to the Wimbledon semi-finals last month, the 38-year-old Serb swapped the whites for a sleek all-black outfit and managed physical issues to prevail under the Arthur Ashe Stadium lights.
Djokovic, seeded seventh, shrugged off a time violation to consolidate an early break at the start of the contest and a heated debate with the chair umpire shortly afterwards only spurred him on to wrap up the opening set in double quick time.
The 19-year-old Tien, on a near-impossible mission to hand Djokovic his first opening-round loss at a Grand Slam since the 2006 Australian Open, had his chances to draw level during a draining second set but crumbled in the tiebreak.
After treatment for a nasty right foot blister, Djokovic produced some heavy groundstrokes from the baseline to break for a 3-1 lead in the third set and the four-times New York champion never looked back from there.

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