Nicky Hayden admitted that his lack of progress was becoming frustrating as he struggled in the midfield in the final practice sessions in Qatar.
The Ducati rider was annoyed that he had been able to get to the bottom of his set-up issues even after two days of testing and two practice days.
"Things didn't really go a lot better today," he said. "My position is worse than yesterday, and my lap time is hardly any better.
"I'm still having trouble with the bike in the long corners, but honestly, a rider should be able to find a bit more time than I have. After two days of testing and the practice sessions, my time isn't that much better than it was in the test.
"It's a bit frustrating to be so far back for the first race, but the team and I will try to figure it out."
Though pessimistic about his qualifying chances, Hayden hopes that a relatively minor change could unlock the bike's performance.
"My guys are working hard and everybody's pitching in," he said. "Qualifying could be difficult because the soft tyre doesn't really seem to help my lap time a lot. Hopefully we can find a setup change or something that will help."
Hayden was six places behind team-mate Valentino Rossi in today's final session, though their times were less than 0.3 seconds apart in the closely-matched middle pack.
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