Lewis Hamilton says his return to the track on Friday in Abu Dhabi felt like "a first day back in school" although the Mercedes quickly adjusted to his familiar environment.
Hamilton got the green light to race this weekend in F1's finale after spending 10 days in isolation after testing positive for COVID-19-19 in Bahrain.
The seven-time F1 world champion said he was "very happy and grateful just to be back".
However, it wasn't a day of clean running for Hamilton whose car suffered from a brake issue early on in FP1 which required some work, while a technical gremlin dogged the end of his FP2 session.
"It felt like a first day back to school kind of thing," he told Sky F1. "So it definitely took a minute to get back used to it for the first session, and then the second one, I think [I was] still getting my bearings, but not too bad.
"I think we got through most of the stuff we missed out in the 40 minute session [shortened by his brake issues] at the start of the day, but otherwise got most of the stuff done."
"It’s definitely been a bit of a messy day with a lot going on," he added.
"The guys have obviously been on the road for three weeks so we’ve had a couple of gremlins but we come through like we always do and tomorrow, I know, will be better.
"We got through a lot of things that we need to test for next year today. The guys are just working as hard as they can to work on things for next year."
Asked to provide his thoughts on the performance at Sakhir of his stand-in George Russell, Hamilton praised the young Briton for a job well done.
"I think George did an amazing job, I think everyone knows that," he replied.
"For me, in my 27 years of racing I’ve never missed a race. One day I’ll write a book about it. But as I said I’m just grateful to be back."
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