Marc Marquez never expected to be leading the MotoGP riders' championship after the opening two races having suffered pre-season problems.
The two-time world champion was less than impressed with his Repsol Honda during testing, the Spaniard particularly struggling with power in Malaysia.
However, Marquez has claimed podiums in both races of the 2016 season and sits top of the standings by eight points courtesy of his victory in Argentina on Sunday.
"If you said to me, 'you would lead the championship' in February, when we were in Malaysia, I would say to you, 'you are crazy'," he told Autosport.
"But we worked really hard during this pre-season, in the Qatar race and [in Argentina] we continued to work hard."
And Marquez hopes to continue that form in Austin this weekend, a track he has won at in each of the last three seasons.
"It's a track that I like, where I feel strong, and where I've always had good races and good fun," he told the team's official website.
"That said, the track rewards strong acceleration, which hasn't been one of our strongest points so far this year, so we'll have to wait and see how we can manage the situation.
"We'll keep working hard, as we did in Argentina, and we'll try to find the best pace for the Sunday race."