Home hero Kato denied by mystery problem.

Daijiro Kato retired from the Pacific Grand Prix after his machine suffered a mechanical problem on lap seven of the Pacific Grand Prix, finally pulling him out on lap nine.

The local rider, who had qualified on pole, was challenging for his first MotoGP win at the time, making his retirement a particular disappointment to him and his team.

"That was a really unlucky day," said a dejected Kato. "I would have liked to have taken my first MotoGP win in front of my own public. I thought I would have the perfect chance after taking pole position and having such a perfect warm-up. Something broke on the bike and I had to return to the garage. I'm really worried and I hope to do better in Malaysia."