RAMPANT Nick Kyrgios has bulldozed Rafael Nadal to reach the Western & Southern Open semi-finals in Cincinnati on a watershed day for the fiery Australian.
Kyrgios wrecked Nadal's hopes of celebrating his return to world No.1 with a blistering 6-2 7-5 victory only hours after completing a rain-delayed 4-6 7-6 (8-6) 6-3 over Ivo Karlovic.
Kyrgios will now face Spanish veteran David Ferrer for the right to chase his first Masters Series title against either Grigor Dimitrov or John Isner.
If the Canberran wins in Cincinnati, he will climb to a career-high mark of No.12 ahead of next week's US Open.
Untouchable on serve with 10 aces, Kyrgios lost only five first-serve points to control 10-time French Open champion Nadal, who returns to No.1 on Monday for time since 2014.
Despite still being hampered by hip soreness, Kyrgios again showcased extraordinary talent.
His advance came as Sam Stosur abandoned her US Open quest.
The 2011 Flushing Meadow champion, Stosur hasn't played since fracturing her hand during the French Open in June.
"Obviously I am extremely disappointed to have to pull out of the US Open," Stosur said.
"The US Open holds such special memories for me and it is a tournament I really look forward to every year.
"It will be tough to miss another grand slam, but while my hand is slowly getting better I know it is in my best interest to keep rehabilitating it.
"I am practising but unfortunately still feeling some pain on certain shots."
Victorians Destanee Aiava, Arina Rodionova and Olivia Rogowska and Queensland's Lizette Cabrera will contest the semi-finals of Tennis Australia's US Open wildcard playoff.
Star teenager Aiava overwhelmed Kimberly Birrell 6-1 6-1 to earn a crack at Rodionova, who advanced with a walkover after Patricia Hon's impressive run in Vancouver forced her withdrawal.
Rogowska downed fellow Melburnian Jaimee Fourlis, who was rusty after not playing since the French Open.
Rogowska faces Cabrera, who downed Ellen Perez 6-4 6-4.
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