Naomi Osaka did not enjoy the fairytale return she hoped for at the Australian Open as the twice-champion lost 6-4 7-6 to French 16th seed Caroline Garcia in the opening round on Monday.
Osaka returned to the tour after 15 months out during which she had her first child and the four-time Grand Slam champion looked rusty at times in her first appearance at a major since 2022 as Garcia capitalised to ease through the first set.
The two players were more evenly matched in the next but it was Garcia who stepped up a gear in the tiebreak to go through.
"I thought it was a really good match and I thought I did as well as I possibly could," Osaka told reporters.
"The competitor in me is not happy that I'm not winning these matches (but) I think I just need to work hard and play a lot more matches and then hopefully my dreams will come true," the Japanese former world no. 1 added.
Coco Gauff first made a big splash at Melbourne Park in 2020 with an upset of holder Osaka and the 19-year-old American, who claimed her first major at the US Open last year, romped into the second round on day two.
Fourth-seeded Gauff admitted to making a nervous start in the first match on Rod Laver Arena but quickly hit her stride to rattle off the last nine games for a convincing 6-3 6-0 win over Anna Karolina Schmiedlova.
Marketa Vondrousova, another new member of the Grand Slam champions club, made a humbling exit after crashing out to Ukrainian qualifier Dayana Yastremska.
The Czech was the first unseeded player to win the women's trophy at Wimbledon last year but found the shoe on the other foot as she succumbed to a 6-1 6-2 upset loss.
"I didn't practice much before the tournament because I was injured," said Vondrousova, who pulled out of a warm-up event with a hip issue.
QUALIFIERS SHINE
The 2024 crop of qualifiers has caused a host of problems for top players on the opening two days of the tournament, not least Dino Prizmic's defiance of 10-time champion Novak Djokovic over four hours on Sunday night.
Third seed Daniil Medvedev was perhaps fortunate that his opponent, Terence Atmane, retired injured during his opening match on a sunbathed Margaret Court Arena.
The French qualifier, who had taken the first set off the 2021 US Open champion before Medvedev levelled the contest, was holding his own in the third when he began suffering severe cramps in his thigh.
The 22-year-old struggled on for almost an hour but finally called time on his first Grand Slam main draw match while trailing the Russian 5-7 6-2 6-4 1-0.
"I played badly at the start of the first set," Medvedev said. "When I started feeling better physically, he started cramping. It was brutal conditions out there."
Local hopeful Alex De Minaur, who stunned Djokovic at the United Cup in the build-up to the Grand Slam, also went through when his opponent, Milos Raonic, retired injured.
Greek seventh seed Stefanos Tsitsipas went a set down in his match against lucky loser Zizou Bergs but produced a remarkable shot from his opponent's side of the net to help turn the tide before running out a 5-7 6-1 6-1 6-3 winner.
"It wasn't easy out here," said the 2023 runner-up at Melbourne Park. "But that determination and that fire sparkled in the second set."