The Australian has been involved in a succession of controversial incidents during his turbulent career, but finally appears to be fulfilling his potential ahead of the hard court tournament in New York.
Kyrgios has prepared well for the final Grand Slam of the year, adding his second ATP Tour title at a warm-up competition in Atlanta earlier this month.
Victory over the big-serving John Isner in the final would have supplied a further confidence boost to Kyrgios, who claimed his maiden ATP trophy in Marseille, back in February.
Kyrgios has not made a big impact in any Grand Slams this year, with a fourth round showing at Wimbledon being his best performance so far, although he will not look back fondly on that one-sided defeat to eventual champion Andy Murray.
The talented 21-year-old has never progressed past the third round at the US Open and will be expected to break new ground at Flushing Meadows.