Djokovic, the tournament's top seed, rolled past Colombia's Santiago Giraldo 6-3, 6-2, 6-1. The world No. 1 player has now won 34 of his last 36 Grand Slam matches and is seeking a third straight Grand Slam title and a third Aussie crown.
Ferrer had a little more trouble in his match, dropping a hard-fought first set before outlasting American Ryan Sweeting 6-7 (4-7), 6-2, 3-6, 6-2, 6-3. Sweeting recorded nine double faults and hit 73 unforced errors in the loss.
Also on Thursday, France's Jo-Wilfred Tsonga, the tournament's sixth seed, defeated Ricardo Mello of Brazil 7-5, 6-4, 6-4 in straight sets, and ninth- seeded Serb Janko Tipsarevic took down Australia's own James Duckworth 3-6, 6-2, 7-6 (7-5), 6-4.
A pair of seeded players were ousted in the tournament's fourth day as 32- seeded Russian Alex Bogolomov dropped the first two sets of his match before taking the next two, but faltered in the fifth set to take a marathon 6-1, 6-3, 4-6, 5-7, 6-4 defeat at the hands of France's Michael Llodra. Spain's Marcel Granollers, the 26th seed, was defeated by Portugal's Frederico Gil 6-3, 4-6, 6-4, 6-3.
In other matches Thursday, 23rd-seeded Canadian Milos Raonic downed Germany's Philipp Petzschner 6-4, 5-7, 6-2, 7-5, Argentina's Juan Ignacio Chela, the 27th seed, rolled to a 6-4, 6-4, 6-3 decision over Spain's Pablo Andujar and Nicolas Mahut of France earned a 1-6, 7-6 (8-6), 6-2, 6-2 decision over Japan's Tatsuma Ito.