After the players exchanged breaks of serve early on -- the Australian playing a lax seventh game to concede his -- Kyrgios made the decisive break of the first set in the tenth game. Kyrgios took the second on a single break and had the chance to wrap things up in straight sets when he served for the match at 5-4.
But the Czech, at 37 Kyrgios' senior by 16 years, broke back and took the third set in a marathon tie-break 11-9, luring Kyrgios to the net with one of many drop shot before passing him with a cross-court forehand.
That burst of energy seemed to tire the Czech, and Kyrgios -- who next plays Germany's unseeded Dustin Brown -- stormed through the fourth set with two further breaks of serve to wrap up victory in two hours and 26 minutes.