Injured MotoGP champion Jorge Lorenzo endured a painful return to action at Laguna Seca on Friday, less than a week after undergoing his second collarbone surgery.
The reigning world champion completed the morning session in a sore 11th before carefully upping the pace in the afternoon to finish in sixth, 0.427s from title leader Marc Marquez.
Significantly, Lorenzo did not use painkillers, in order to gauge his level of endurance.
“It was much better this afternoon [than in the morning]. I tried to improve step by step like I did in my first time in MotoGP here to try to minimise the risk and understand the limit of the track. Every lap it got better and better, but obviously the pain is there.
“I felt a little better than this morning but not so much, after seven laps it started to be difficult to brake. I struggled a lot in braking but still we were able to practice without painkillers, this is very positive because with the painkiller we will get some benefits.
“The bike is working really well, we are just losing some tenths in some braking points where we cannot push too hard. The balance of the day is pretty good considering my physical condition.”
Team manager Wilco Zeelenberg said: “We are very pleased with the result, it's a very hard track when you have injuries. So to be in his position, in sixth place and staying calm is good. We need a good practice tomorrow to find a good setting and a good pace. I think the race will be very tough.”
Title rival Dani Pedrosa, also carrying a collarbone injury from last weekend's German round, sat out the morning session and was eleventh in the afternoon. Marquez leads the standings by two points from team-mate Pedrosa and eleven from Lorenzo, whose team-mate Valentino Rossi was fourth quickest.