Max Verstappen said that Red Bull's RB16 "felt better" after the troubled car was updated with a few new aero parts, but a botched lap ruined the Dutchman's best effort in FP2.
Verstappen set the pace in the morning session by a comfortable margin of almost half a second over Mercedes' Lewis Hamilton.
The 22-year-old looked on track to repeat the feat in the afternoon practice but was forced to abort his fastest lap after stumbling upon a slow-moving Romain Grosjean on the racing line.
But overall, Verstappen was happy with his opening day of running.
"I got blocked on my fast lap and then moved on to race runs, so I don’t have a proper time on the board for FP2 but in the end that doesn’t matter on a Friday and it wasn’t a bad day for us," Verstappen commented.
"We keep developing and bringing new parts to the car and they seem like they are working a bit better, so I’m happy with that and the direction.
"There are of course still things that we can improve and on a Friday you don’t know what the others are doing.
"We will keep working but overall the car looked and felt better today. On the long runs we also looked quite decent but who knows what the weather will be like for the rest of the weekend and how that will change things!
"Overall, I would say it was a positive day but we will see where we really are tomorrow."
Verstappen's team mate Alex Albon was among the front-runners in the morning and had just put the fastest time on the board in FP2 when his session came to a brutal end when he spun and heavily hit the barrier.
"I’m fine and it wasn’t that bad," he said. "The rear just went away quite quickly and I struggled to correct it. I thought I caught it and then I just got sent into a tank slapper.
"We’ll have a look at the data and see what happened there."
Despite the mishap, Albon was encouraged by the step-up in performance of Red Bull's RB 16.
"I think we’ve definitely made a step," he added. "We expected worse coming into today but the car feels good and it was hooked up straight away from the first lap in FP1.
"Obviously I’m pretty sure the Mercedes are hiding a lot so we’ll be watching them tomorrow but otherwise on our side the car feels more balanced and I think we have a better understanding of it.
"The wind and temperatures tomorrow will be very different to what we’ve had today so it will be a little bit of a reset but it’s looking good so far."
Gallery: The beautiful wives and girlfriends of F1 drivers
Keep up to date with all the F1 news via Facebook and Twitter
Helmut Marko believes that Red Bull and Max Verstappen are unlikely to challenge for victory…
Automotive giant General Motors is reportedly back in the game as a potential entrant in…
The opening day of running at the Las Vegas GP was a smooth but chilly…
Williams is continuing to fight uphill battles this weekend in Las Vegas as a knock-on…
It was a solid start to the Las Vegas weekend for Ferrari with Carlos Sainz…
Lando Norris didn’t hold back in his assessment of McLaren’s performance on the opening day…