George Russell admitted Mercedes are “scratching our heads” after the W15 car flew out of the blocks in practice in Las Vegas on Thursday night.

Lewis Hamilton topped both FP1 and FP2 around the Las Vegas Strip Circuit, holding a significant gap to the Mercedes’ rivals in first practice in particular, before maintaining top spot in the more representative FP2 session.

George Russell: Mercedes ‘scratching our heads’ over Las Vegas GP pace

Free practice was typified by low grip in the cold conditions in Las Vegas, with drivers often struggling to apply the throttle and brake without locking up with the streets of Las Vegas dusty and holding a low track temperature.

The Mercedes duo were able to make the most of the two hours of running, however, with a one-two in FP1 followed up by both drivers in the top three in the second session.

Mercedes’ pace caught the attention of Red Bull’s Helmut Marko, who conceded that the W15 is looking “really strong” in Nevada.

Marko told Austrian outlet ORF: “We’ve often seen this from Mercedes this year, that they are suddenly extremely strong and capable of winning.

“But let’s wait and see how it goes tomorrow. The more grip there is on the track, the order can change again.”

Russell said the W15 was able to perform from the off on Thursday night, and while he stressed it was just free practice, it was a “pleasantly surprising” evening for the team.

“Incredible day. [I would] love to tell you why, we’re scratching our heads a little bit why it was so positive,” Russell admitted after FP2.

“Obviously, it was only practice. Lewis did a really great job out there as well, he’s been really on it since lap one today, but the car’s just been working.

“We’re on a street track, it’s really dirty, it’s getting faster and faster every lap.

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“Because we were fast today, it doesn’t necessarily mean we’re going to replicate it tomorrow, when the track will be probably three seconds faster. Pleasantly surprising.”

It is not the first time this season Mercedes have been strong at the start of the weekend, only for their performance to tail off relative to the likes of Ferrari, McLaren and Red Bull.

Russell believes the reputation of the Silver Arrows seeing their returns diminish at certain weekend this season is not a representative one, given the differences between the cars involved in practice running.

This time around, however, he is hoping the team can hold onto its early promise heading into qualifying on Friday night in Las Vegas.

“I think the perception of us losing performance is maybe not quite fair,” he said.

“I think it’s more of a function that our competitors don’t use their high power.

“They might be running a bit more fuel than us on a Friday, so historically, they’ve been sandbagging a little bit more and when they take it off, they go into their normal position.

“There’s a possibility that will happen again tomorrow, but the gap we showed this morning, and this evening, has been pretty substantial.

“I’m sure the other rivals are going to work hard overnight and close that gap, and I just hope we can continue the form.”

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