Ducati says poor set-up cost Stoner

The Australian started from the front row but lost ground in the early laps and could only recover to fifth.

"With the wet set-up it was a gamble and it didn't work, so despite Stoner being very strong in the wet he struggled a lot," Suppo told Italia1.

"In the dry he had to modify the steer damper, when he slowed on the straight he was overtaken by Chris [Vermeulen], after which he did very well and got the second best race lap. Unfortunately it was a missed chance. He usually is super strong in the wet, but it happens when you don't get a chance to test in the wet."

Suppo said Stoner had been very upset about the result, but could understand his frustration.

"Casey has matured a lot but today he hasn't done the race he did in Japan where he had a technical problem and he was very good at avoiding exaggeration, or at Jerez where he had a super race," said the team boss.

"Here unfortunately he's very upset because he couldn't find a good wet set-up, but it happens. He's certainly matured a lot, but he's obviously very young still.

"He's won the championship when he was still a kid, only [Freddie] Spencer could do better. Last year he perhaps wanted to dominate, while this year he's grown up a lot."

Nicky Hayden only managed 12th on the second Ducati. He ran in the top ten at first, but fell back after he picked up damage when Mika Kallio (Pramac Ducati) crashed while dicing with him.

"Hayden was a bit unfortunate, because when Kallio fell he collided a bit with him, so he has a big mark on the bodywork, and a wire got ripped," Suppo explained.

"So nothing serious, but he had the discs dirty for a while. The performance is still far from what we expected, but we're working. He is certainly more positive, he's had a decent warm-up. It's clear that after such a difficult start of the season he needs to regain his confidence."