Serena Williams continued her smooth passage through the Australian Open draw but Bianca Andreescu and Petra Kvitova fell in the second round.
Williams, whose one-legged catsuit is inspired by former sprinter Florence Griffith Joyner, has been in a hurry so far and dropped just five games in her first two matches.
She was tested in the first set on Wednesday by 99th-ranked Serbian Nina Stojanovic but cruised thereafter to win 6-3 6-0 and set up a third-round clash with Russian teenager Anastasia Potapova.
Former US Open champion Andreescu made her long-awaited return after 15 months out but became the latest big-name scalp claimed by the supremely unorthodox Hsieh Su-wei.
The 35-year-old’s use of spins and angles is unlike anyone else in the game and it was a test too far for Andreescu at this stage of her comeback.
The 20-year-old Canadian rallied after losing the first four games but all her attempts at a comeback were thwarted as she lost 6-3 6-2.
She said: “I got off the court and I was looking at my coach, and I said, ‘I’m just disappointed, that today was my all’, because I know I gave my all today and to me I think that was the most disappointing part.
“She played really well. I have to give credit to her. I definitely have to get back into the groove of things, and hopefully that will be sooner (rather) than later.”
Andreescu rocketed up the rankings in a remarkable 2019, culminating in her run to the title in New York, but has suffered a worrying number of injuries for such a young player, with a knee problem behind her lengthy lay-off.
The eighth seed said: “I think now it’s just getting back into play, and it’s good to know that I still have that fighting spirit in me. I feel really good. After my first round I thought I would feel more exhausted but I felt amazing.
“I don’t feel at my best on the court for sure, but I’m super happy that I’m finally back after being off for so long. It’s just such an amazing feeling being back, doing what I love.”
Ninth seed Kvitova reached the final in Melbourne in 2019 and the quarter-finals last year but her tournament is over already after a 6-4 1-6 6-1 defeat by Romania’s Sorana Cirstea.
Seventh seed Aryna Sabalenka has been one of the form players of the last few months and she reached the last 32 with a 7-6 (5) 6-3 victory over Daria Kasatkina.
Marketa Vondrousova ended the run of Canadian qualifier Rebecca Marino, who won her first grand slam match for 10 years in round one after mental health problems forced her away from the sport.