Melbourne - Naomi Osaka conceded she had been "a bit childish" after her frustrations boiled over on Wednesday in setting up a third-round showdown with teenager Coco Gauff at the Australian Open.
The reigning champion handled the blustery Melbourne conditions to defeat China's 42nd-ranked Zheng Saisai 6-2, 6-4.
But the 22-year-old Japanese was irritated by Zheng's defensive play and her emotions got the better of her when the Chinese broke early in the second set.
Osaka threw her racquet to the floor, then gave it a kick for good measure.
The two-time Grand Slam champion also tossed away a ball and slammed the racquet down again as she slumped to her chair, covering her head with her towel.
"My racquet just magically flew out of my hand," Osaka said mischievously, smiling.
"I couldn't control it, I think that's how I dealt with my frustration.
"It was a bit childish. I just want to play one match without throwing my racquet or kicking it. That's all I want."
The former world No 1, seeded third for the defence of her Melbourne title, said that Zheng's way of playing - "slicing and dicing and getting everything" - had riled her.
"It's really tough because you start thinking - she's not hitting winners."
"I definitely got very frustrated in the second set and it's something that I knew would happen," Osaka added.
"But I didn't know the scale, what she would do to make me frustrated."
Results on day three of the Australian Open Grand Slam at Melbourne Park on Wednesday:
Tennys Sandgren (USA) bt Matteo Berrettini (ITA x8) 7-6 (9/7), 6-4, 4-6, 2-6, 7-5
Sam Querrey (USA) bt Ricardas Berankis (LTU) 7-6 (7/2), 4-6, 6-4, 6-4
Guido Pella (ARG x22) bt Gregoire Barrere (FRA) 6-1, 6-4, 3-6, 6-3
Marton Fucsovics (HUN) bt Jannik Sinner (ITA) 6-4, 6-4, 6-3
Tommy Paul (USA) bt Grigor Dimitrov (BUL x18) 6-4, 7-6 (8/6), 3-6, 6-7 (3/7), 7-6 (10/3)
John Millman (AUS) bt Hubert Hurkacz (POL x31) 6-4, 7-5, 6-3
Stefanos Tsitsipas (GRE x6) bt Philipp Kohlschreiber (GER) walkover
Milos Raonic (CAN x32) bt Cristian Garin (CHI) 6-3, 6-4, 6-2
Marin Cilic (CRO) bt Benoit Paire (FRA x21) 6-2, 6-7 (6/8), 3-6, 6-1, 7-6 (10/3)
Diego Schwartzman (ARG x14) bt Alejandro Davidovich (ESP) 6-1, 6-4, 6-2
Dusan Lajovic (SRB x24) bt Marc Polmans (AUS) 6-2, 6-4, 6-3
Yoshihito Nishioka (JPN) bt Daniel Evans (GBR x30) 6-4, 6-3, 6-4
Novak Djokovic (SRB x2) bt Tatsuma Ito (JPN) 6-1, 6-4, 6-2
Roger Federer (SUI x3) bt Filip Krajinovic (CRO) 6-1, 6-4, 6-1
Fabio Fognini (ITA x12) bt Jordan Thompson (AUS) 7-6 (7/4), 6-1, 3-6, 4-6, 7-6 (10/4)
Roberto Bautista Agut (ESP x9) bt Michael Mmoh (USA) 5-7, 6-2, 6-4, 6-1
Sara Sorribes (ESP) bt Veronika Kudermetova (RUS) 2-6, 6-1, 6-1
Anett Kontaveit (EST x28) bt Astra Sharma (AUS) 6-0, 6-2
Iga Swiatek (POL) bt Timea Babos (HUN) 6-3, 6-2
Carla Suarez (ESP) bt Aryna Sabalenka (BLR x11) 7-6 (8/6), 7-6 (8/6)
Elise Mertens (BEL x16) bt Danka Kovinic (MNE) 6-2, 6-0
Heather Watson (GBR) bt Kristyna Pliskova (CZE) 4-6, 6-3, 6-1
Anastasia Pavlyuchenkova (RUS x30) bt Nina Stojanovic (SRB) 6-1, 7-5
Taylor Townsend (USA) bt Jessica Pegula (USA) 6-4, 7-6 (7/5)
Ashleigh Barty (AUS x1) bt Polona Hercog (SLO) 6-1, 6-4
Elena Rybakina (KAZ x29) bt Greet Minnen (BEL) 6-3, 6-4
Alison Riske (USA x18) bt Lin Zhu (CHN) 6-3, 6-1
Julia Goerges (GER) bt Petra Martic (CRO x13) 4-6, 6-3, 7-5
Maria Sakkari (GRE x22) bt Nao Hibino (JPN) 7-6 (7/4), 6-4
Ekaterina Alexandrova (RUS x25) bt Barbora Krejcikova (CZE) 6-1, 6-3
Petra Kvitova (CZE x7) bt Paula Badosa (ESP) 7-5, 7-5
Naomi Osaka (JPN x3) bt Saisai Zheng (CHN) 6-2, 6-4
Cori Gauff (USA) bt Sorana Cirstea (ROU) 4-6, 6-3, 7-5
Shuai Zhang (CHN) bt Caty McNally (USA) 6-2, 6-4
Sofia Kenin (USA x14) bt Ann Li (USA) 6-1, 6-3
Ons Jabeur (TUN) bt Caroline Garcia (FRA) 1-6, 6-2, 6-3
Caroline Wozniacki (DEN) bt Dayana Yastremska (UKR x23) 7-5, 7-5
Qiang Wang (CHN x27) bt Fiona Ferro (FRA) 6-1, 6-2
Serena Williams (USA x8) bt Tamara Zidansek (SLO) 6-2, 6-3
Madison Keys (USA x10) bt Arantxa Rus (NED) 7-6 (7/3), 6-2