No. 4 seed Novak Djokovic of Serbia eased past Flavio Cobolli of Italy 6-1, 6-2 to cruise into the men's singles fourth round at the Shanghai Masters in east China's Shanghai Municipality on Tuesday.

Djokovic took an early lead in the opening set by leveraging the baseline exchanges with clean strikes from both wings. The quick opener encouraged him to put more pressure on Cobolli in the second set. Though the Italian managed to hold serve twice, he failed to resist Djokovic's aggressive attacks in the fifth game, seeing another smooth triumph for his opponent since then.

"Great level of tennis I think from me from the beginning. I had a clear game plan of what I need to do and how to execute it," Djokovic said, adding that the long match last night affected the Italian's physical condition.

Entering the fourth round, Djokovic will meet Roman Safiullin of Russia. "I have played him a couple times before, so I know his quality. He loves to play fast, take the ball on the rise, so I have to be very sharp for that one," Djokovic noted.

Second-seeded Alexander Zverev of Germany survived a close match that included two tiebreaks against Tallon Griekspoor of the Netherlands 7(8)-6, 2-6, 7-6(5) in the third round of the tournament. It was Zverev's fifth win over the opponent in their six meetings.

"It was a tough match, going back and forth. I thought he was a bit lucky during the third set and I got very lucky in the tie-break, so we equaled each other out," the German said. "It was an incredible match, he is someone that I always struggle against. We always have extremely tough matches and, for me, he should be a lot higher ranked than he is. He needs to look at why he is not playing like that every single week. He could be Top 15, Top 10 in the world."

Zverev will play David Goffin of Belgium next.