Novak Djokovic moved into the fourth round with his most confident performance of the week,against the 26th-seeded Tomas Machac.

MELBOURNE, Australia — Count Novak Djokovic as being in Danielle Collins' corner. He thinks her response to booing fans at the Australian Open was absolutely fine — which should come as no surprise, given the way Djokovic gets into back-and-forths with hecklers at his matches, including Friday night at Rod Laver Arena.