Casey Stoner admitted that his confidence was shaken by his crash during qualifying for the British Grand Prix.
The Australian had a fall in practice as well, and although he went on to qualify fourth with his spare bike, he was frustrated after the session.
"This morning was a little bit difficult, we were struggling with set-up a lot and I didn't feel very comfortable," said Stoner. "This afternoon we changed the bike a bit and the first part of the session the bike was feeling really good. Not perfect -- we were struggling with rear grip, but we know that's an issue we've had at the moment that we're struggling to get rid of. But the bike was turning a lot better and I was feeling a lot better at most places.
"I went back out there for a lap, it didn't feel right, the front end seemed to have too much pressure on it and I didn't feel comfortable. But you never know what kind of lap time you're putting out even if the bike doesn't feel the best, so I went into McLeans, definitely not as fast as I had been before, and just lost the front."
The spare Ducati had a set-up which Stoner was less comfortable with, hampering his efforts to get back into the pole battle.
"That was the only bike that we had in that set-up and geometry," he explained. "Unfortunately my second bike was completely different so we couldn't get anywhere near what we had on my number one bike and just had to make do.
"I already wasn't happy with the number two bike's set-up and wanted to go in another direction. But because it's completely different geometry that was no time to change it before the end of the session."
He said it hard been hard to get back on the pace following the incident.
"To be honest, we're pretty happy to get back to where we did. It wouldn't have taken much more to get on the front row," said Stoner.
"I lost a bit of a confidence and it's quite hard to get back from that. I lost the front for no reason this morning, I lost the front again down the Craner Curves in qualifying.
"So I wasn't really looking forward to pushing again, so I just sucked it up a little bit and tried to get on the front row if we could, but fourth is the next best."
He is confident that returning to his preferred setup will get him back on the pace for race day.
"I'm not too worried because we know the set-up we had at the start of the session was good, it was just the one we went to later," said Stoner. But he did admit that his physical condition remains an issue.
"This weekend it's feeling quite a bit different to the Sachsenring," said the Ducati rider. "I think the weather and layout helped me there. This weekend we're finding more of a struggle.
"It wasn't even hot today, but it was hot enough to get me into a sweat and I was slowing down. This weekend we haven't been able to find a setup and it has taken its toll."