It was smooth sailing for the two top seeds on day three of the US Open.
Novak Djokovic needed just over an hour and a half to get past Andreas Haider-Maurer in straight sets.
The Serbian was ruthless on serve in the 6-4 6-1 6-2 win.
Women's world number one Serena Williams was tested by Dutchwoman Kiki Bertens,
Who forced a tiebreaker in the opening set.
But Williams found her groove to storm through the second set 6-3 for her 50th win on tour this year and 30th straight in all majors.
