Farah sidesteps the danger to smash British record in style

Somali-born runner races to a nerveless victory in the 5,000m in Monaco on a dramatic night featuring season’s-best for Usain Bolt and a bizarre punch-up

The action was not just fast but pretty furious as the IAAF Diamond League series pitched up in Monaco last night.

The men's 5,000m had both ingredients. Americans Galen Rupp and Chris Solinsky came to grief – one sent sprawling to the track in the Stade Louis II stadium, the other barged on to the in-field – as the field jostled for position. Amid all of the aggravation, Mo Farah kept the coolest head, hitting the front with 500m remaining, resisting the challenge of Bernard Lagat, the former world 1500m and 5,000m champion, and claiming victory in 12min 53.11sec.

In doing so, the Somali-born, London-raised Farah took a chunk of 4.83sec off the British record figures he set for the distance in Zurich in August last year. It was the 28-year-old's second British record of the summer, having smashed Jon Brown's 10,000m mark in Eugene in May. There was also a second British record of the season for Tiffany Ofili-Porter, who finished third in the 100m hurdles in 12.60sec.

That made it two British records in little more than five minutes in Monaco last night, and eight in all so far this summer – a promisingly mounting tally a year away from a home Olympic Games. The chances are Farah will break another before the season is out.

Last summer he was a class apart in Europe, winning the 5,000m and 10,000m titles at the continental championships in Barcelona. This year, since hitting the Oregon trail and joining the group of elite American distance runners guided by the former marathon great Alberto Salazar in Portland, the Londoner is proving to be a class apart at a global level.

At one point of the race last night, Farah eased to the front of the field to ask why the pacemakers had slowed. Quite clearly, he has a good deal more left in the tank as he works towards the World Championships in Daegu, South Korea, next month and, of course, those home Olympics in 2012.

"It's going well," Farah said. "Alberto's been looking after me. I'm just disappointed about my training partner [Rupp]. I saw him fall right in front of me."

The real fury, though, came earlier in the evening – with the astonishing sight of Mehdi Baala and Mahiedine Mekhissi coming to blows after finishing ninth and 11th respectively in the 1500m.

Watched by Prince Albert and the newly-crowned Wimbledon champion Novak Djokovic, a Monaco resident, Baala aimed a head-butt and threw a punch at Mekhissi. An ugly scrap ensued and the pair had to be pulled apart. Quite what sparked the confrontation was not immediately clear, although the two French team-mates and rivals are known to be far from the best of friends.

It was an astonishing sight to behold – one that made the continuing spat between Phillips Idowu, the world triple jump champion, and Charles van Commenee, the head coach of UK Athletics, seem more like a John and Yoko love-in.

Idowu was a member of the British legion in action in Monaco and the 32-year-old Belgrave Harrier emerged a comfortable winner, courtesy of a second round jump of 17.36m.

It would be difficult to imagine Usain Bolt becoming engaged in any kind of confrontation, physical or verbal. The laid-back Jamaican was also a comfortable winner, taking the 100m in 9.88sec, a season's best for the man who holds the world record at a freakish 9.58sec.

Ofili-Porter's British record came in a 100m hurdles race stacked with world-class talent. As the in-form Australian Sally Pearson sped to victory in a scorching 12.51sec, with Kellie Wells of the US second in 12.58sec, the American-born Ofili-Porter was pulled along to third place in 12.60sec – an improvement of 0.17sec on the national record time she set at Hengelo in the Netherlands in May.

Sadly for Dai Greene, a bout of illness that forced him to skip training earlier in the week left the Welshman too flat to have a crack at Kriss Akabusi's 19-year-old British record in the 400m hurdles. Still, the Swansea Harrier showed his fighting spirit, gritting his teeth in the home straight to take third place in 48.43sec – behind Olympic champion Angelo Taylor, who prevailed in 47.97sec, and another top-notch American, Bershawn Jackson, the runner-up in 48.22m.

Away from the Diamond League circuit, there was a gold medal for Great Britain on day two of the European Junior Championships in Tallinn yesterday. Jodie Williams surged to victory in the women's 100m final, lowering her lifetime best to 11.18sec in the process. "My times in training have been better than last year, so I knew I had it in me," the 17-year-old Hertfordshire schoolgirl said. There was also silver and bronze for Adam Gemili and David Bolarinwa in the men's 100m final.

Back at home, there was some sobering news for British sprinting. UK Athletics announced that Bernice Wilson, a 60m semi-finalist at the European Indoor Championships in Paris in March, had been provisionally suspended after testing positive for the anabolic steroid clenbuterol and for excessive levels of testosterone. The 27-year-old Birchfield Harrier has the right to appeal but now faces a two-year suspension and a lifetime Olympic ban.