Cal Crutchlow was left to reflect on a 'stupid mistake' after the Tech 3 Yamaha rider fell while holding fourth place in the Catalunya MotoGP.

Crutchlow, who started from second place on the front row, was in pursuit of Yamaha's Jorge Lorenzo and Repsol Honda pair Dani Pedrosa and Marc Marquez when the 27-year-old clipped the kerb at Turn 7 and crashed out in the opening stages.

He still remains in fourth position in the championship on 71 points and is aiming to get back on track at round seven of the series at Assen.

"Obviously I am disappointed that a great weekend ended with a crash and I have to hold my hands up and say it was a stupid mistake on my part," said Crutchlow.

"Like last season and again in the first few races of 2013, I have been struggling to stop the bike in the early laps with a full fuel load.

"I was giving it my all to stay in the battle with the top three and unfortunately I hit the kerb on the inside and crashed.

"It was a silly mistake and I am sorry to the team because I am confident I could have stayed in the fight for the podium right to the end."

Despite the setback, Crutchlow remains confident he can challenge for more rostrum honours at Assen.

"We have got to understand why we don't have so much grip at the start of the race but I can take some big positives out of the weekend again," he said.

"I was on the front row, I was fastest in the warm-up and I was battling for the podium in the race.

"Now we can go to Assen confident that I will have good speed and be in the rostrum fight again."

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