Britain's Olympic 5,000 and 10,000m champion had described his meeting with the two Ethiopians leading this year's standings, Hagos Gebrhiwet and Yenew Alamirew, as "the real thing" - and he needed a final 400m of 52.36sec and a final 200m of 27.26 to hold off his challengers as the cagey proceedings formed themselves into a sprinting race.

With a crowd near its capacity of 12,000 roaring support, Farah kicked on as Alamirew came up to his shoulder on the final bend and crossed the line in 13min 14.24sec, a stride ahead and with just enough time for his trademark "Mobot" pose.

Mo Farah wins the 5000m at the IAAF Diamond League meeting in Birmingham ahead of Ethiopia's Yenew Alamirew

"It was important that I won the race," said the relieved Farah.

"It was a tough field so I'm really pleased I came through it with a victory.

"It's important that I keep working hard now and get ready for the World Championships.

"I got a massive roar from the crowd which was good.

"It reminded me of the atmosphere at the Games, I've got great memories from London so that was great today."

But while Farah rose to the challenge, other Olympic and world champions were unable to maintain their gold standard.

Botswana's world 400m champion Amantle Montsho suffered her first defeat in this year's Diamond League when she was beaten on the line by the fast-finishing home runner Christine Ohuruogo.

Urged on by the crowd, the Olympic silver medallist and former champion closed on Montsho over the last 80m and leaned ahead to win by a hundredth in 50.63.

Jamaica's Olympic 100m gold medallist from London, Sally-Ann Fraser-Pryce, suffered her first defeat of the year after six consecutive wins, being beaten over 200m by Blessing Okabare.

The Nigerian crossed the line in 22.55sec to beat the labouring Fraser-Pryce who clocked 22.72 in second.

World 100m champion Carmelita Jeter - still recovering from the thigh injury she suffered six weeks ago - had an even worse time of it than Fraser-Pryce as she finished back in seventh.

Another global champion, Australia's Sally Pearson, found the going tough on a blazing afternoon in the Midlands.

Olympic 100m hurdles champion Sally Pearson (centre) could only finish fourth in Birmingham on a day when a host of other champions faltered

The world and Olympic 100m hurdles champion endured her worst defeat for three years when she could only finish fourth behind the American pair of Dawn Harper-Nelson and Kellie Wells, with Britain's Tiffany Porter taking third.

Pearson had won her injury comeback race in Ostrava three days ago in 12.67 and was only six hundredths slower here, but Harper-Nelson and Wells surged ahead of her from half way to clock 12.64 and 12.67 respectively.

Porter ran a season's best of 12.72.

Meanwhile, Pearson's male counterpart Aries Merritt, the London 2012 110m hurdles champion, has also had injury problems and that was reflected in a performance which saw him beaten by 2009 world champion Ryan Brathwaite of Barbados, who clocked 13.13 to the American's 13.22.

In the men's 400m hurdles there were defeats for both the Olympic champion, Felix Sanchez, and Britain's world champion Dai Greene in a race won in 48.60 by the man Greene beat in Daegu two years ago, Javier Culson of Puerto Rico.

Britain's European champion Rhys Williams finished second, close to his personal best in 48.93.

Sanchez struggled home seventh in 49.68 while Greene was fifth in 49.55.

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