Dimitrov broke serve early in set one to lead 4-2 before closing out the set after only 34 minutes of play.
At 2 all in set two, Kyrgios struck two aces at speeds of 133 and 127 miles per hour to hold serve at love to lead 3-2.
Then serving at 4 all, once again Kyrgios struck back to back aces, this time both down the tee at speeds of 131 and 136 miles per hour to hold serve at love and lead 5-4.
Dimitrov followed up with a service hold of his own to level the set at five games all.
In his following service game, Kyrgios’ all or nothing tactic would prove a key to his defeat. The heavy hitter struck his 15th ace; a 123 miles per hour down the tee winner but also double faulted three times to go down 30-40.
On breakpoint, Kyrgios powered a 126 miles per hour serve down the tee. However his following crosscourt forehand landed long as he lost serve to trail 5-6.
Serving for the match, Dimitrov struck a 91 miles per hour down the line on the run forehand winner to lead 30-0.
Then on match point number two, Kyrgios netted an inside out crosscourt forehand to end the 50 minutes long set. The match itself had lasted for one hour and 24 minutes.
“Going to the (US) Open, it’s for sure a lot of positivity with it,” added Dimitrov, who did not drop a set all week.
“But the most important thing now is just to stay grounded, keep on doing the same work, believe in myself, and just prepare the best way that I can for the Open."