Almaz Ayana was the undoubted star performer on the first day of track and field action at Rio 2016. We summarise the main developments.
- Ethiopia's Almaz Ayana shocked the world on the opening day of athletics action at Rio 2016, taking more than 14 seconds off the women's 10,000 metre record to claim gold in stunning fashion.
- Two-time gold medallist Valerie Adams of New Zealand was surprisingly dethroned as the women's shot put champion as Michelle Carter set a new American national record of 20.63m with her final throw to dramatically snatch gold.
- Day one of the heptathlon ended with reigning Olympic champion Jessica Ennis-Hill in pole position, 72 points ahead of Nafissatou Thiam of Belgium with Akela Jones and Katarina Johnson-Thompson also in contention.
- Two-time reigning champion Shelly-Ann Fraser-Pryce was the fastest qualifier from the women's 100m heats, with a time of 10.96 seconds.
- Greg Rutherford, the winner of the men's long jump at London 2012, squeezed through to Saturday's final as the 10th-best qualifier, after two no jumps had put him under huge pressure.
- Friday's two sessions at the Olympic Stadium both failed to pull in the crowds, with a host of empty seats visible throughout.
It could only be Ayana, whose remarkable display in the women's 10,000m left observers staggered. A winning time of 29 minutes, 17.45 seconds was enough to earn victory by over 15 seconds, ahead of Vivian Jepkemoi Cheruiyot and two-time reigning champion Tirunesh Dibaba.
Ayana set the only world record in the Olympic Stadium on Friday, but Carter's winning throw in the shot put represented a new best for the United States. Johnson-Thompson and Thiam each cleared 1.98m in the high jump, a new best for the heptathlon.
QUOTES OF THE DAY
"I don't have any regrets because I did a personal best. One day, one time, I know that I'm going to be an Olympic champion," - Cheruiyot reflects on coming second to the unstoppable Ayana.
"That was awful. It was embarrassing. I was far too slow for the first 200 - I could see the guys in front and I was like 's***'," - British runner Martyn Rooney makes his feelings clear after failing to make the semi-finals of the men's 400m.
"I can't imagine what my mum's doing right now. I can guarantee she's crying," - Carter expects the tears to flow following her shock shot put success.
The women's 100m final stands out as the pick of Saturday's action, while Mo Farah will be fancied to retain his 10,000m title. The heptathlon also draws to a close in an action-packed evening session.