Williams defeated older sister Venus in straight sets, 6-4, 6-4, on Saturday night as Lunar New Year celebrations began.
Roger Federer has proved king of Melbourne Park, winning his fifth Australian Open singles title and 18th grand slam in an epic five-set battle against old foe Rafael Nadal on Sunday night.
Before the finals, the world no. 17 told reporters if he was to win against Nadal, it "would be super special and very sweet" because he hasn't beaten the Spanish stalwart in a Grand Slam since Wimbledon in 2007, and suffering defeat the last three times they met at the Australian Open.
"It would have been nice for both of us to win (as we're both on a comeback), but there's no draws in tennis, it's brutal sometimes," Federer told reporters after winning 6-4, 3-6, 6-1, 3-6, 6-3 in three hours, 38 minutes.
"He should be happy. I would have been happy again to be in the finals," thus "this one will take more time to sink in."
"The magnitude of this match is going to feel different. I can't compare this one to any other one except for maybe the French Open in 2009. I waited for the French Open, I tried, I fought, I tried again and failed. Eventually I made it. This feels similar."
It started as a tense battle in the first set where neither player was willing to push too hard in fear of giving the other a break, before Federer managed to exploit Nadal's weak side, rushing the net and attacking his backhand before firing a winner on the other side of the court in the seventh game.
Nadal responded in the second however, taking the first four points of the set. Federer had a chance to break back in third point after the Spaniard sent the ball too deep with the Swiss ace running to the net, but two consecutive errors on increasingly aggressive play allowed Nadal to save serve. Federer took one break back in the fifth game with a winner, but Nadal held on.
The Australian crowd became more animated in the third, pushing Federer to save two break points in the first game -- Nadal fired a forehand straight into the net -- when his net play wasn't working, only to break the world No. 9's serve the next game.
Things went from bad to worse for Nadal, only saving one game, the first time he was held to a 1-6 set score since a fourth round loss at last year's U.S. Open to frenchman Louis Pouille in five sets.
It was after that match he sidelined himself to recover from a plaguing wrist injury that forced his retirement from the 2016 French Open, despite "taking risks" to play the 2016 Rio Olympic Games where took gold in the doubles.
"If I won that one (Australian Open final), (that) will be amazing, but the real thing that makes me more happy, more than titles, is go on the court and feel that I can enjoy the sport," Nadal told reporters.
"Today I am enjoying the sport.
"At this moment in my career... more than all these kind of things (winning titles) is being healthy enough to work the way I need to work, to fight for the things I want to fight. I'm going to keep trying to do and to work the same way."
Nadal responded in the fourth set, exploiting net play of Federer while the Swiss was taking more and more risks, pushing the ball ever so wide while attacking the Spaniards forehand, sending it to a deciding, and thrilling fifth.
Federer took an off-court medical time out in the set break, something he said in just his previous match didn't help for his groin injury that he had been nursing throughout the match, but may clear the mind to focus on what was ahead.