Novak Djokovic beat Stefanos Tsitsipas for the ninth straight time by 6-4, 7-6 (4) in the players’ opening match at the ATP Finals on Monday.
Djokovic has beaten Tsitsipas in his third straight tournament following wins in Astana, Kazakhstan and at the Paris Masters.
“All the matches we’ve played have been decided by two or three points and that was again the case tonight,” Djokovic said.
He broke Tsitsipas in the opening game and held from there to close out the first set.
“A break in these conditions is decisive,” Djokovic said of the fast indoor court.
A cross-court backhand passing shot winner that landed on the line helped Djokovic move ahead in the second-set tiebreaker.
Tsitsipas won two of his first three career matches against Djokovic but hasn’t beaten the 21-time Grand Slam winner in more than three years.