Repsol Honda's Casey Stoner got his MotoGP title defence off to a slow start in Qatar with arm pump comprimising his pace and bringing his braking performance down to 'pathetic'.

The Australian was feeling the effects from early on and his inability to brake properly meant the front-end chatter his team had dialled out in warm-up returning with a vengeance allowing both Jorge Lorenzo and Dani Pedrosa to steam past with four laps to go.

"We got rid of a load of the front-end chatter earlier in the day but during the race it got worse and worse, and that was because I wasn't able to be on the brakes long enough, unloading the front earlier, getting on to the edge of the tyre earlier and then it would just chatter. It would have been less of an issue if I could have held on to the brakes but I was pathetic on the brakes at the end of the race. I couldn't believe they didn't just steamroller past on lap ten," said Stoner, speaking to bikesportnews.com at Losail.

"The pump started very early on in the race, maybe lap three or four I started feeling the first signs. I did one lap hard and dropped everyone, and I thought they weren't able to run my pace. Then I rolled back but the pump got worse and worse, and I was struggling to hold on. I was going into corners not being able to feel how much brake pressure I was putting on."