The meeting lasted 3 hours 12 minutes and ended with the score 3: 6, 6: 4, 3: 6, 6: 4, 6: 2 in favor of the 28-year-old Bulgarian tennis player.
Dimitrov's rival in the semifinals will be Russian Daniil Medvedev.
Earlier, Medvedev admitted that he could not finish the match with Stan Wavrinka.