Lewis Hamilton set the pace in Friday practice for the season-ending Abu Dhabi Grand Prix.
Lewis clocked a 1:37.877s to edge Ferrari's Sebastian Vettel to the top spot by +0.149s. Daniel Ricciardo was just was just a tenth back in third, on a tight-fought final Friday of the season.
Vettel pipped Lewis to the top time in the opening session, but Lewis smashed the circuit record to end the day on top.
"It's been a good Friday, but I'm happy that it's the last one of the season," said Lewis. "We got lots of laps in today and made good progress with the balance of the car.
"We have a bit of work to do, but I feel like we're quite competitive here. It's relatively close still, but I like that.
"Especially for this weekend, I've got a helmet with gold leaf for the World Championship, which I'm really grateful for."
Valtteri was the first driver to complete a qualifying run in the evening, but slipped to fifth as first Vettel and then Lewis improved.
"We dedicated the first practice session to testing for next year," said the Finn. "We ran different kinds of mechanical and especially aero tests. So we didn't learn that much for this weekend in FP1, but definitely a lot for next year.
"The second session was more straightforward. I was missing a bit of time in the last sector, so as a team we need to work on that. The temperatures here are ok; it's definitely warm in the cockpit, but we've been to worse places.
"Overall, it's been a pretty good day, we just need to find some more pace from my side for tomorrow."
While Lewis hit the ground running around Yas Marina, Trackside Engineering Director Andrew Shovlin says there is still work to do to be ready for qualifying, and what should be another tight battle with Ferrari and Red Bull.
"A busy day for the drivers and everyone in the garage," said Andrew. "We had a large development programme focused on 2018, this required both cars to devote the entire P1 session towards this work but despite the ambitious programme, we managed to get through it all successfully.
"The track cools significantly into the evening session and our focus shifted towards qualifying and race preparation. The car seems to be working reasonably well although we've got plenty of areas we can look to improve overnight.
"Valtteri in particular was not comfortable with how the car was handling on a single lap so we have a bit of work to do there. Lewis found the car more predictable on low fuel but there are still some areas that we can find a bit of time.
"The long run balance was quite consistent but it's difficult to know where everyone is as there seemed to be a lot of traffic out there today and many cars were struggling to string clear laps together.
"We are expecting another tough battle for pole tomorrow, having seen strong times posted by both Red Bull and Ferrari through the sessions, but we are determined to finish the season on a high and will make sure we give it our best shot."