Novak Djokovic beats Van de Zandschulp to enter Astana Open quarterfinals

Add Botic van de Zandschulp to the long list of players to have been schooled by Novak Djokovic.

Djokovic eased past Van de Zandschulp 6-3, 6-1 on Thursday in his first career meeting with the 27-year-old Dutchman to reach the quarterfinals of the Astana Open.

Van de Zandschulp earned one break point in each set but couldn't seriously threaten Djokovic, who is looking for a second straight indoor hardcourt title after winning in Tel Aviv last week.

(In the) second set I think I started to read his serve better and just started swinging through the court more, Djokovic said. Botic is a quality tennis player. When he has time, he can hurt you, so I tried to take away that time from him and I'm very pleased with the way I played, particularly in the second.

Djokovic will next face Karen Khachanov, who rallied to beat Marin Cilic 2-6, 6-3, 6-3. If the 21-time Grand Slam champion gets past that one, he could come up against fellow former No. 1 Daniil Medvedev.

The second-seeded Russian beat Emil Ruusuvuori of Finland 6-3, 6-2 to move one match away from a potential rematch of last year's U.S. Open final, when Medvedev beat Djokovic to deny his attempt at a calendar-year Grand Slam.

Medvedev will first have to beat Roberto Bautista Agut, who advanced Wednesday.