With track temperature rising and the main men going out on soft tyres, laptimes tumbled in the second MotoGP free practice session of the day at Austin with Marc Marquez leading team-mate Dani Pedrosa and LCR's Stefan Bradl in a Honda clean sweep.
Marquez is now getting closer to the times he set during testing in March, ending on a 2'05.031 with his penultimate circuit with Repsol teamster Pedrosa half a second down and Bradl a further 0.5s in arrears.
Yamaha pairing of Jorge Lorenzo and Valentino Rossi completed the top five and it was the top five who tested at the Texas track in March but neither of the champions could get close to Marquez, with Lorenzo 1.6s off the pace and Rossi another two-tenths further back.
Britain's Cal Crutchlow is meeting his expectation of being the best of the rest in sixth place and 1.8s off the pace with a 2'06.899. Andrea Dovizioso had a couple of technical problems with his bike and had to park it on the back straight but still managed to get out on his second bike to bag seventh place.
Alvaro Bautista is in eighth place with Nicky Hayden and Ben Spies rounding out the top ten. Bradley Smith put is Monster Yamaha in 13th place and is 4.3s slower than Marquez.
Aleix Espargaro, who suffered with some brake problems early on, came back at the end to take CRT top spot followed by Yonny Hernandez and Randy De Puniet. Michael Laverty improved to 20th while Colin Edwards slipped to 23rd.