World No. 18 Karen Khachanov of Russia dropped out of the ATP-500 tournament in Astana, Kazakhstan.
In the quarterfinals Khachanov lost to 21-time Grand Slam winner Novak Djokovic 4-6, 3-6. The match lasted one hour and 20 minutes.
In the semifinals, the opponent of the Serbian tennis player will be the winner of the match Daniil Medvedev (Russia) - Roberto Bautista Agut (Spain).
The prize fund of the tournament in Astana is $1.9 million.