The American, 39, said it was “vintage Serena” as she thrashed the German 6-1 6-1 in front of a small, unmasked crowd on Rod Laver Arena.
US Open champion Naomi Osaka also made a convincing start with a 6-1 6-2 win over Russia’s Anastasia Pavlyuchenkova.
But former champion Angelique Kerber was the first seed to be knocked out.
The German 23rd seed, who was one of 72 players to spend 14 days in ‘hard’ quarantine before the tournament – confined to a hotel room and unable to train outside – was beaten 6-0 6-4 by American Bernarda Pera.
Kerber, a three-time Grand Slam champion, said the quarantine had affected her form for the major.
“You feel it, especially if you play a real match where it counts and you play against an opponent who doesn’t stay in the hard lockdown,” she said.
American 24th seed Alison Riske, who also did the hard quarantine, lost 6-2 6-1 to Russian world number 101 Anastasia Potapova.
French Open champion Iga Swiatek raced into the second round with a 6-1 6-3 win over Arantxa Rus of the Netherlands, but US Open quarter-finalist Tsvetana Pironkova of Bulgaria lost 7-5 6-2 to Taiwanese Hsieh Su-wei.
Hseih will next play Canada’s Bianca Andreescu, who beat Mihaela Buzarnescu 6-2 4-6 6-3 in her first match for 15 months.
Second seed Simona Halep raced into the second round with a 6-2 6-1 win over Australian wildcard Lizette Cabrera in just 59 minutes.
Czech Petra Kvitova, who was runner-up to Osaka in 2019, also advanced by beating Greet Minnen of Belgium 6-3 6-4.
Seventh seed Aryna Sabalenka of Belarus was also victorious on the first day, beating Slovakia’s Viktoria Kuzmova 6-0 6-4. (Courtesy BBC)