John McEnroe's ex-wife Tatum O'Neal reacts to Venus Williams remembering Olympics 2000 triumph with Serena Williams

John McEnroe's former wife and actress Tatum O'Neal recently reacted to Venus Williams remembering her first Olympics triumph with sister Serena Williams as her partner.

The year was 2000 and the venue was Sydney. Venus Williams and Serena Williams had already won three Grand Slams together and were competing in the Olympics for the very first time in their respective careers.

The duo were unseeded in the women's doubles event but went on to win the gold medal, defeating the Dutch duo of Kristie Boogert and Miriam Oremans 6-1, 6-1 in the final. This was the fourth successive Olympics where an American pair had won gold in the women's doubles event.

Venus Williams also clinched the gold medal in the women's singles tournament, beating Elena Dementieva 6-2, 6-4 in the final. The 43-year-old took to Instagram to remember her doubles triumph with Serena Williams on the 23rd anniversary of the event.

"On this day in 2000, Sydney @Olympics gold medal with my baby sis @serenawilliams So special. And then in singles," Williams captioned an image of herself and Serena Williams on the podium in Sydney.

Tatum O'Neal commented on the image with a simple heart emoji.

Tatum O'Neal's comment on Venus Williams' image

Tatum O'Neal, who is the youngest-ever Academy Award winner, was married to former World No. 1 John McEnroe from 1986 to 1994. The couple had three children, whose custody McEnroe eventually went on to win.

Serena Williams and Venus Williams won four Olympic gold medals each

Serena Williams and Venus Williams celebrate their women's doubles triumph in 2012

Serena Williams and Venus Williams are both decorated Olympians, winning four gold medals each.

After winning the women's doubles event in 2000, they clinched gold eight years later, in Beijing, beating Anabel Medina Garrigues and Virginia Ruano Pascual in the final. Both sisters were eliminated in the quarterfinals of the singles tournament that year.

They successfully defended their doubles title at the 2012 Olympics in London, beating the Czech pair of Andrea Hlavackova and Lucie Hradecka in the gold medal match. Serena Williams also won the women's singles tournament by thrashing Maria Sharapova 6-0, 6-1 in the final.

The 2016 Olympics in Rio de Janeiro was the last appearance for the Williams sisters at the prestigious event. They suffered early exits in singles, with Venus Williams losing in the first round and Serena Williams exiting in the third round.

The legendary duo were the top seeds in the women's doubles event but suffered a first-round exit at the hands of eventual bronze medalists Lucie Safarova and Barbora Strycova.

Venus Williams, however, did manage to win the silver medal in the mixed doubles event, partnering Rajeev Ram. The pair were beaten by compatriots Bethanie Mattek-Sands and Jack Sock in the final.