Novak Djokovic sent an ominous warning to his rivals that this year's US Open would not be a two-horse race after ruthlessly disposing of James Blake on Saturday.
The No.3 seed is slowly building momentum as he seeks to reach a second final in New York, where he was runner-up in 2007.
On a day in which five-time champion Roger Federer cruised through in tricky conditions, Djokovic strolled past Blake 6-1 7-6 (7-4) 6-3 on Arthur Ashe Stadium to progress to the fourth round in just 104 minutes.
The Serb took the first set in just 22 minutes but later exercised caution as his normally aggressive game took a back seat.
"If he (Blake) won the second set it would have been a different match," Djokovic said.
He hit just 12 winners compared to Blake's 27 - but Djokovic forced several errors from the American who went for his shots.
The third seed praised his serve for helping him in key moments of the game.
"A couple of points here and there decided the second set and I was fortunate enough to serve well when I needed too," he said.
Djokovic now faces another American, 19th seed Mardy Fish, in the round of 16 after he won a five-set encounter against Arnaud Clement 4-6 6-3 6-4 1-6 6-3 in more than three-and-a-half hours.
Earlier, Federer easily accounted for Frenchman Paul-Henri Mathieu 6-4 6-3 6-3 to stay on course for a quarter-final showdown with his French Open conqueror Robin Soderling.
Federer hit 31 winners and 13 aces against Mathieu, who upset 32nd seed Lleyton Hewitt in the first round.
Federer will take on Austrian Jurgen Melzer in the round of 16 after he toppled Spaniard Juan Carlos Ferrero 7-5 6-3 6-1.
But it is the potential quarter-final clash with Soderling that has whetted everyone's appetite.
The fifth seed ended Federer's streak of 23 consecutive Grand Slam semi-final appearances at the French Open this year.
Soderling had a comfortable 6-2 6-3 6-3 win over the Netherlands' Thiemo de Bakker to set up a clash with 21st seed Albert Montanes, who moved after Kei Nishikori retired hurt with the score at 6-2 2-1.
"Everybody has been telling me since the draw came out I'm going against Roger in the quarters," Soderling said. "It's still far ahead."
"I'm the fifth seed, so I know I'm gonna play one of the four top guys in the quarters. They're all good players so it doesn't really matter who I'm playing."
Gael Monfils ended Janko Tipsarevic's run 7-6 (7-4) 6-7 (4-7) 6-2 6-4.
The first two sets proved an entertaining battle before errors crept into Tipsarevic's game and Monfils improved his serve as the Frenchman made the fourth round for the third successive year.
Monfils will face compatriot Richard Gasquet who won a lengthy battle against South African Kevin Anderson 6-4 7-6 (7-3) 7-5.