China’s Wu Minxia splashed into the Olympic record books on Sunday, passing legends like American Greg Louganis and “big sister” Guo Jingjing as the most decorated diver in history.

Wu became the first person with five diving gold medals thanks to a no-doubt victory with partner Shi Tingmao in the women’s synchronised 3m springboard that kicked off the Rio Games competition and China’s hopes of an eight-medal sweep.

“I’m really happy to get this medal. We all wished that the Chinese divers would have a good performance during the Olympic Games,” Wu said afterward.

The result establishes her as one of the great all-time Olympians and sets a number of new diving milestones.

She passed the now-retired Guo to become the first man or woman with seven total diving medals, and is now the only diver to win four golds in a single event.

At the age of 30, she also became the oldest women’s winner in Olympic diving history, and Wu admitted feeling those years in the run-up.

“I thought about giving up before these Olympic Games because I got injured for a month and I thought it would take a lot of time to recover. It’s really hard to maintain my best performance,” she said.

Sunday’s easy victory could help Wu emerge from the shadow of her former synch partner Guo.

Guo captivated China with her dominance in the pool in Athens and Beijing, her glamourous diving-diva aura, and penchant for upsetting officials in China’s state sports apparatus.

Wu herself was at the centre of controversy in 2012 when it was revealed that her parents hid the news of her grandparent’s death and her mother’s cancer battle so she could focus on the London Games.

The revelation touched off a debate in China over the country’s win-at-all-costs mentality in the Games.

Wu had nothing but praise for Guo after surpassing her one-time mentor.

“Guo Jingjing always helped me tremendously in the early stages of my career. She has always taken care of me and helped my grow,” Wu said.

“Even though now I may have bigger achievements in the Olympics, she will always be ‘big sister’ to me.” Wu won’t be able to add to her medal tally in Rio as Sunday’s competition was her sole event. She said she was likely to retire.

Wu’s five gold medals take her one past Guo, compatriots Fu Mingxia and Chen Ruolin, Louganis, and Patricia McCormick of the USA.

Chen could catch Wu on five golds later in Rio when she competes in the 10m synchronised event.

Wu won the 3m synchronised springboard in 2004 and 2008 with Guo, and in 2012 with He Zi. Wu’s other gold came in the London 2012 3m individual springboard.

Wu and Shi leapt to the top of the leaderboard from round one on Sunday and never let up, locking it away in the last two rounds with exquisitely synchronised dives that had the judges fawning.

Their final tally of 345.60 points was 31.77 more than Italian silver medallists Tania Cagnotto and Francesca Dallape. Maddison Keeney and Anabelle Smith of Australia took bronze.

Serena and Venus Williams were deposed as Olympic Games women’s doubles champions on Sunday, their hopes of a fourth gold dashed by Lucie Safarova and Barbora Strycova in the first round.

Just a day after 36-year-old Venus, suffering from a virus and stomach complaint, was beaten in the singles, the top-seeded sisters slumped to a 6-3, 6-4 defeat against the Czech pair.

The sisters won the Olympic doubles title in 2000, 2008 and 2012.

Serena is the defending champion in singles while Venus was the title winner in Sydney 16 years ago.

South Korea’s top swimmer Park Tae-hwan apologised to his compatriots after bombing out of another race at the Rio Olympics on Sunday. “I was afraid of looking up at the scoreboard,” he told the Yonhap news agency after finishing last in his 200 metres freestyle heat. “I didn’t want to come out of the pool.” Park’s presence in Rio has been controversial, the country’s first Olympic swimming medallist winning a late battle to compete after appealing against a doping ban.

The 2008 gold medallist in 400m freestyle failed to qualify for the finals in that event on Saturday after clocking the 10th-fastest time.

On Sunday he was 29th overall in the 200m, a time 2.31 seconds slower than Chinese pacesetter Sun Yang, ending his hopes of winning a medal in the distance for the third Games in a row after silvers in 2008 and 2012.

Park completed an 18-month ban imposed by world governing body FINA in March after testing positive for testosterone ahead of the 2014 Asian Games.

Under a controversial Korean Olympic Committee regulation, he was then hit with an additional three-year ban from the national team the day the FINA suspension expired.

That would have ruled him out of contention for Rio but the Court of Arbitration for Sport cleared the 26-year-old to compete. He is also due to swim in the 100m and 1,500m freestyle races in Rio. “I wanted to put yesterday’s 400m race behind me,” he said on Sunday. “But I think I was trying too hard to make up for it and my shoulders didn’t move the way I wanted them to.”