NEW YORK - Teenage standard-bearer Nick Kyrgios is Australia's last man standing at Flushing Meadows after Roger Federer ended big-serving Sam Groth's gallant US Open campaign.
Try as he might, Groth was unable to find a way past the mighty Federer, faltering 6-4 6-4 6-4 in his "once-in-a-lifetime" appearance under lights at Arthur Ashe Stadium.
After cracking the world's top 100 this month, Groth was facing a top-10 rival for the first time — and opponents don't come any tougher in New York than the masterful Swiss.
The five-times champion boasts the Open's greatest winning strike rate — a staggering 89 per cent — in 46 years of professional tennis and has lost only once in 25 night matches.
And dressed to kill in undertaker all-black, Federer was in a merciless mood as he broke Groth's much-hyped serve five times in an entertaining duel.
Federer was so majestic that even Groth's best rally ended in defeat when the second seed flicked a breathtaking half-volley backhand lob over his head after the Australian thought he had him pinned.
Groth, the owner of the world's fastest serve, also fired down a 236.5kph bullet, the most explosive delivery of the tournament.
But he lost that point too as Federer carved out another straight-sets victory, just like his opener against Marinko Matosevic, to set up a fourth-round date tomorrow with Spaniard Marcel Granollers.
With Bernard Tomic withdrawing from his scheduled second-round meeting with Spanish fourth seed David Ferrer earlier yesterday, Kyrgios is now the lone Australian left in the men's singles draw.
The 19-year-old takes on Spanish 16th seed Tommy Robredo on Saturday night for a place in the last 16.
While Ferrer remains on track for a semi-final encounter with Federer, sixth-seeded Czech Tomas Berdych is also lurking in the bottom half of the draw after scraping through a sapping five-setter with Slovakian Martin Klizan.
Berdych, who took out Federer in the 2012 quarter-finals, plays Russian Teymuraz Gabashvili next after progressing 6-3 4-6 6-2 3-6 6-3 yesterday.
Wimbledon semi-finalist Grigor Dimitrov is also through to the last 32, the Bulgarian seventh seed routing Israeli Dudi Sela 6-1 6-2 6-2.