Rio Olympics 2016: Kyle Edmund and Heather Watson win

Great Britain's Kyle Edmund and Heather Watson have both reached the second round of the Olympics singles.

Edmund won 6-4 6-2 against Australian Jordan Thompson, while Watson beat China's Shuai Peng 6-4 6-7 (5-7) 6-3.

Watson also won in the women's doubles alongside Johanna Konta, the pair beating Serbia's Jelena Jankovic and Aleksandra Krunic 6-2 6-1.

British number ones Andy Murray - the defending champion - and Konta both play in the singles on Sunday.

• Day-by-day guide to what's on

Murray, who beat Roger Federer in the final at London 2012, begins his men's singles campaign against Serbia's Viktor Troicki on Sunday.

Tenth seed Konta meets Liechtenstein's Stephanie Vogt, who is ranked 290th in the world, in the women's singles.

Edmund, 21, will play Japan's world number 118 Taro Daniel next, while 24-year-old Watson, the world number 67, faces a higher-ranked opponent in Ukraine's Elina Svitolina.

British number two Watson eventually saw off Peng after seeing four break points wiped out in the final two sets

Doubles defeat for British men

Watson returned to court a few hours after her singles victory when she teamed up with Konta.

The pair needed just 65 minutes to beat Jankovic and Krunic, setting up a potential second-round tie against third seeds Hao-Ching Chan and Yung-Jan Chan of Chinese Taipei.

But Colin Fleming and Dom Inglot are out of the men's doubles, beaten 6-3 6-0 by Mexico's Santiago Gonzalez and Miguel-Angel Reyes Varela.

Meanwhile, fifth seed Venus Williams suffered a surprise first-round defeat by Belgium's Kirsten Flipkens in the women's singles.

The 36-year-old American, who is also playing in the doubles alongside sister Serena, lost 6-3 4-6 7-6 (7-5).

The USA tennis coach Mary Joe Fernandez said Williams, who has Sjogren's syndrome, was poorly coming into the competition.

"She's not feeling well," she said. "She's been ill for quite a few days. Two days prior to coming here she was really sick with a bad virus.

"You could probably see she was coughing up a lot. She did everything possible to try and win this match. She got dehydrated. She's cramping a bit and is getting sick to her stomach.

"She's used to not playing at 100% with her Sjogren's. I think that's why we saw her compete and fight until the end."

Another big-name exit saw Poland's Agnieszka Radwanska, the fourth seed, lose 6-4 7-5 to China's world number 64 Saisai Zheng.

In the men's singles, Japanese fourth seed Kei Nishikori and ninth seed Marin Cilic, who is representing Croatia, both advanced on the opening day.

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