The top seed Novak Djokovic has roared into the fourth round of the U.S. tennis Open with a 6-0 6-2 6-2 victory over Joao Sousa of Portugal.
The 26-year-old Serb, who has yet to lose a set, smacked 34 winners to just 10 for the 95th-ranked Sousa in the 100-minute rout.
The Australian Open champion Djokovic faced just two service breaks, while converting eight of 13 against his opponent.
Djokovic next faces either 43rd-ranked Marcel Granollers of Spain or 109th-ranked American wild card Tim Smyczek.
Elsewhere the defending champion Andy Murray set-up a US Open last-16 showdown with Uzbekistan's Denis Istomin, the world No.65.
The third-seeded Briton eased past Germany's world number 49 Florian Mayer, 7-6 (7-2) 6-2 6-2 to reach the fourth round.