Thomas Rohler of Germany earned a dramatic javelin victory with a huge fifth round effort of 90.30 metres, but in the other field event of the night, the women’s high jump, Spain’s 37-year-old Ruth Beitia - who briefly retired after just missing the podium at London 2012 - claimed her first global gold by clearing 1.97m.

Action in the Olympic Stadium concluded with US victories in the men’s and women’s 4x400m relays.

Not only did Farah match Viren’s Olympic record, he also contrived to fall en route to winning the 10,000m at almost exactly the same point as the Finn had before getting up and claiming gold.

Tonight, with no Kenyans qualified for the race, it was up to the Ethiopians to try and work out a way of beating the ebullient Somalia-born Londoner who has not lost a global final since little known Ethiopian Ibrahim Jeilan surprised him near the line in the 10,000m at the 2011 International Association of Athletics Federations World Championships in Daegu.

"The strategy was to go fast and drop Mo Farah," said Hagos Gebrhiwet, whose task was shared by team mate Dejen Gebremeskel.

"In the first six laps we tried our best but when we couldn't see any change, we held it back then."

A relatively slow race leapt into life at the bell as Farah, who had stayed in touch with the lead all the way through, began a long run for home.

He entered the home straight, as so often before, trailing challengers who remained only that before crossing in 13min 03.30sec for gold.

"It's every athlete's dream but I can't believe it," Farah said.

"I wasn't going to let the inside lane go. I didn't want to get boxed in."

The identity of the silver and bronze medallists took more than an hour to determine as Paul Chelimo of the United States, who moved briefly alongside Farah in the home straight before fading back, and Gebrehiwet took respective silver and bronze in a personal best of 13:03.90 and 13:04.35.

Post-race, Chelimo discovered he was one of three runners disqualified for putting a foot inside the track while he was being interviewed by NBC TV.

He immediately vowed to appeal - which he and fourth-placed Mohammed Ahmed of Canada eventually did with success.

In the meantime, however, 41-year-old US runner Bernard Lagat briefly moved up to take bronze and become the oldest medal winner in any track event at the Olympic Games.

Soon both medal and record were gone, but Lagat reacted with class.

"To disqualify people when they didn't gain an advantage is not the right spirit," Lagat, winner of a bronze medal at Sydney 2000 and silver at Athens 2004, said. 

"I like to know I earned my medal."

At least he is spared that moral dilemma now…

Centrowitz, winner of the world indoor 1500m title in March, was part of the giant pack which had been trundling round the track for 1,000m before the racing began in earnest at the bell.

The 26-year-old American moved into the lead and kept it all the way to the line in a 1500m version of the earlier 5,000m, with Taoufik Makhloufi, the defending champion, closest of his pursuers.

With a last lap of 50.62sec, Centrowitz crossed for gold in 3:50.00, with Makhloufi taking silver in 3:50.11 and bronze going to Nick Willis of New Zealand in 3:50.24.

Kenya’s Beijng 2008 gold medallist Asbel Kiprop could only manage sixth in 3:50.87, lost in the press for the line. 

A big surprise.

Centrowitz earned the first men's Olympic 1500m gold for the United States since Mel Sheppard at London 1908. 

"There's nothing like it," he said

"It doesn't compare to anything else I've won in my life.

"Doing my victory lap, I literally kept screaming to everyone I know, 'Are you kidding me?'"

Semenya was in full control of the women's 800m final at the bell, leading on the inside with her big rival Francine Niyonsaba of Burundi at her shoulder.

Into the final straight, and the figure in green motored to the front, stretching her lead to five metres at the finish in a South African record of 1:55.28, the fastest time of the year, with Niyonsaba taking silver in 1:56.49.

Bronze went to Margaret Wanbui of Kenya in a personal best of 1:56.89, ahead of Canada's Melissa Bishop, who ran a national record of 1:57.02.

A stupendous fifth round throw of 90.30m from Germany's Thomas Rohler earned the German an astounding gold in the men's javelin.

A first round effort of 88.24m from Julius Yego, Kenya's world champion, looked likely to earn victory until the German's huge effort.

Yego, who had to retire after the fourth round, could only stand and watch as his gold turned silver, although he had won Kenya’s first ever Olympic medal in a field event.

But no-one else could surpass the German, as the best of the rest, defending champion Keshorn Walcott of Trinidad and Tobago, took bronze with 85.38m, edging ahead of Rohler's team-mate Johannes Vetter, who managed 85.32m.

Beitia, three times European champion used all her experience in reaching the relatively modest winning high jump height of 1.97m with least fouls.

After a third failure at 2.00m, the veteran Spaniard had an agonising wait as three more jumpers tried their luck. 

After Mirela Demireva of Bulgaria and Croatia's former world champion Blanca Vlasic failed, Beitia was silver medallist at worst.

Chaunte Lowe of the US had one final attempt for glory - but failed, dropping down to fourth as gold was confirmed for Beitia and Demireva, for whom 1.97m was a personal best, took silver.

Bronze was a triumph for the vivacious Vlasic after the serious inijuries she has suffered in the last couple of years.

Beitia, who is member of the Parliament of Cantabria back in Spain, announced she was ending her career after clearing 2.00m but missing out on a medal at London 2012. 

After two months, however, she thought better of it. 

Good decision.