Rio 2016: Almaz Ayana smashes women's 10,000m world record to take gold for Ethiopia

Ayana produced an eye-popping run to storm home in 29 minutes 17.45 seconds

Almaz poses next to her new women's 10,000m world record (Getty)

Ethiopia's Almaz Ayana obliterated the 23-year-old 10,000 metres world record to claim the first athletics gold of the Rio Olympics.

Ayana produced a startling run at the Olympic Stadium to storm home in 29 minutes 17.45 seconds, taking more than 14 seconds off the mark set by China's Wang Junxia in 1993.

Vivian Cheruiyot ran a Kenyan record to take silver, but was still more than 15 seconds behind her 24-year-old rival.

The blue track is clearly quick, with the top 13 finishers all running personal bests, but Ayana's display was still barely believable.

Jo Pavey finished 15th as she made history by becoming the first British track athlete to appear at five Olympics.

The 42-year-old mother of two clocked a season's best 31mins 33.44secs.

Pavey, whose team-mates Jess Andrews and Beth Potter finished 16th and 34th respectively, said: "I was aware how soon they lapped us.

"When I heard the time afterwards I couldn't believe it. It's so much faster than you could ever imagine someone would run."

The race featured eight national records and 18 personal bests.

Indeed, Cheruiyot, bronze medallist Tirunesh Dibaba of Ethiopia and Alice Nawowuna, the Kenyan who set the early pace before finishing fourth, all ran times that before this race only Wang had ever bettered.

Earlier this year Chinese state media reported Wang, along with nine team-mates coached by the controversial Ma Junren, had written a letter - penned in 1995 but which had only just come to light - admitting to being an unwilling participant in a state-sponsored doping programme.

Ayana, whose previous PB was 30:07.00, hailed her world record as "a dream come true".

"I never thought that this would happen and I'm so in awe. I'm very happy to get here," she said.

Paula Radcliffe, the marathon world record holder, described the race on Twitter as "mind blowing".

Pavey, who made her major championship debut in 1997, was never a realistic medal contender, but insisted she planned to carry on racing, targeting next summer's World Championships in London.

She said: "I would have liked to have run a bit quicker but realistically I am getting very old.

"When I was a school girl dreaming of going to an Olympic Games I would never have imagined I'd be here having done five. It felt so special to be on that start line.

"It does give me motivation to go on to next year, there's a carrot of it being at home again."

Pavey, the 2014 European champion, had joked in the run-up to the race that when she heard in 2005 that London had won the bid to host the Olympics in 2012 she thought how sad it was that she would not be able to compete at a home Games. Four years after London and she is still going strong.

Qualifying for Rio was a minor miracle itself for Pavey, who had all but given up on selection after being troubled by a chest infection.

A hugely gutsy performance at last month's European Championships in Amsterdam, where she finished fifth, earned her a spot.