Marc Marquez says his Austin test pace is no guarantee of success MotoGP's Grand Prix of the Americas this weekend.
The Spaniard was fastest on all three days of pre-season running at the American circuit, while his overall best was more than half a second clear of team-mate Dani Pedrosa and the two works Yamahas.
Marquez cautioned that changing track conditions, and the physical effects of a full race distance, mean the weekend is no foregone conclusion.
"To arrive on the podium in my first race was a dream come true, but now we must face the reality and focus on the job at hand," Marquez said.
"I am looking forward to going to Austin, it will be interesting as we have already been there testing and we found a good base set-up.
"But we will see because it will be a different scenario with more rubber on the track and the conditions will change.
"The first part, with the chicanes, is where the difference can be made.
"I think that this will be the decisive part of the race as well, because physically this half of the track tires you out and requires constant strength.
"We will concentrate on our work and our own agenda to prepare ourselves in the best possible way for the race."
Stablemate Pedrosa says he is confident the set-up issues that plagued him at Losail have been identified and fixed in time for Austin.
"Qatar was not the start we expected, but I know what the issue was so it's clear for the next race," he added.