Stefan Bradl extended his lead in the Moto2 World Championship with a comfortable win at Barcelona after many of his closest challengers crashed out. The early stages of the race saw over a dozen riders running nose to tail as the intermediate class proved as competitive as ever, but a series of incidents broke up the field and gave Bradl a clear run to the chequered flag.

The German got away cleanly from pole position with Julian Simon leading the chasing group which included front row starter Aleix Espargaro and the two TechnomagCIP Suters of Dominique Aegerter and Kenan Sofuoglu.

Bradley Smith was hung out to dry at the first corner after starting from the second row but the Briton was flying and set the fastest lap to bring himself onto the tail of Thomas Luthi and Yuki Takahashi in eighth place.

His race took a turn for the worse though on lap six when Luthi lost control coming round turn three which collected Takahashi. Both riders were out of the race and Smith was forced to run onto the grass after a slight collision with the Gresini Racing Moriwaki and fell back to 17th.

The top five now had a gap over the rest of the field which was now led by Marc Marquez. The French Grand Prix winner was among the fastest riders on track and was quickly closing in on the leading group and was past Simone Corsi for sixth on lap nine.

Kenan Sofuoglu was the man in the ascendancy as the race passed half distance. The Turkish rider disposed with his teammate Aegerter and Espargaro in successive laps to move up to third and was now challenging Simon for second.

The Technomag team's hopes of a strong result would be dashed on lap 16 though with Aegerter the first to fall at turn five, the same corner that caught out Valentino Rossi and Colin Edwards in MotoGP practice yesterday.

Just a few corners later, Sofuoglu's race came to a sickening end as well. As the riders braked for turn 11 the Turk crashed into the back of Julian Simon's Suter, sending the Spanard flying over the handlebars of his bike. Sofuoglu's machine also hit Simon as it flew through the gravel and the Mapfre Aspar rider was later diagnosed with multiple fractures to his right leg.

Julian Simon is flung from his Suter, Sofuoglu would join him in retirement

Bradl's lead was now up to 2.3seconds with Marquez now up to second ahead of Espargaro. The series of accidents had spread top front three riders apart and there would be no change before the chequered flag, with Corsi a distant fourth.

Attention now turned to the battle for fifth which was led by Esteve Rabat. Randy Krummenacher was close behind him while Smith had charged his way back up to seventh, just ahead of Alex De Angelis and Mika Kallio.

Krummenacher and De Angelis both made their way past Rabat as Smith kept a watching brief behind and the Swiss rider would eventually secure fifth after outbraking De Angelis at turn ten on lap 21.

The JIR rider was now forced to fend off Rabat for sixth and as they entered turn ten for the final time, Smith was forced on to the outside and lost control of the Mistral 610 on the wet kerb, dropping all the way out of the points.

Kallio was promoted up to eighth while Yonny Hernandez and Max Neukirchner completed the top ten. Scott Redding will have been relieved to finally claim his first points of the season in 11th.

Championship contender Andrea Iannone had a miserable race after losing ground in the first two laps but the problems for Bradley Smith on the final lap did at least hand him the final point for 15th. Kev Coghlan finished in 24th position.