Austin, United States: Italy's Andrea Iannone posted the fastest time Friday on his final lap to edge world champion Marc Marquez in practice for Sunday's MotoGP Grand Prix of the Americas.
Iannone rode his Suzuki around the course in 2mins 4.599secs, knocking Spanish Honda-rider Marquez off the top spot by .056 of a second.
Spanish Yamaha rider Maverick Vinales was third, .264 of a second adrift, with Italian teammate Valentino Rossi fourth, .359 of a second off the pace.
Britain's Cal Crutchlow, a winner earlier this month in Argentina to seize the season drivers' points lead entering the season's third race, was fifth on his Honda in 2:05.088.
Marquez has dominated at the Texas track since the event began in 2013, winning all five races from the pole. Only Iannone in 2015 had deprived the Spaniard of a top practice time before repeating the feat Friday.
Even after a minor crash that left him unharmed in the afternoon, Marquez was confident about his chances on the weekend.
"I'm quite happy with how things are going because I felt strong from the beginning, and we worked for the race," Marquez said. "Most importantly, I did my lap time with a hard rear tire.
"Our pace is already good, but there are a few things we want to improve because I don't yet feel 100 percent. I had a small crash when I tried another setup, so we need to keep working."
The top seven laps in Friday's second practice session were faster than Marquez's 2:05.530 that led the first session.
Attention will be upon Marquez and Rossi after the Spaniard knocked the Italian down in Argentina.
"I'm afraid of going out on the track, I'm afraid of running with him, I'm afraid of what might happen to me," Rossi said in Argentina. "I think he believes he runs alone and, in addition, he treats me differently than the others."
Marquez answered: "I thought I made a mistake, I was penalized, I went to apologize and I do not have any problems or resentment in being able to talk with others."