Although quickest in Thursday’s practices in Las Vegas, Toto Wolff is not getting carried away with Lewis Hamilton’s pace – but then again “Spa was cold and Silverstone was cold”.

Mercedes hit the jackpot in Sin City on Thursday night as cold temperatures and a dirty track played to the W15’s strengths.

Toto Wolff says Mercedes are the ‘dirty track champions’

Hamilton set the pace in FP1, his run on the soft tyres late in the session wrapped up with a 1:35.001.

That put him four-tenths up on his Mercedes team-mate George Russell while he was a whopping 0.953s quicker than third-placed Lando Norris. No one else got within a second of Hamilton’s time such was the Briton’s pace in a session in which the track temperature reached a high of 14’C.

Wolff stopped short of crowing when he spoke with the media, including PlanetF1.com, between the two practice sessions.

“I think we are dirty track champions,” said the team boss. “FP1 is always great and then the moment the grip kicks in, we’ve seen that the performances deteriorate.

“Having said that, I think the gap was pretty big. It’s the biggest that we’ve seen so far in FP1, so we’ve got to spray some dust for all the sessions tomorrow, in qualifying or something.

“But I don’t believe this kind of advantage to the other teams is going to last. I would very much hope that we’re not falling behind like we did in the past on some of the tracks, but remain competitive, fight in the front.”

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Wolff was correct in saying that “kind of advantage” would not continue, but Hamilton still finished at the top of the timesheet in FP2, albeit by a slim 0.011s.

With the track temperature plummeting a chilly 11’C, Hamilton posted the fastest time in the late-night session with a 1:33.825. Norris was second with Russell P3.

The good news for Mercedes and Hamilton, Friday and Saturday nights won’t be any warmer with Wolff saying the cold suits the W15.

“It was a pretty good start,” Wolff told F1TV. “But I don’t want to think too much of it.

“We’ve been quick in some of the early sessions during the weekends when there is not a lot of grip so if we can continue to be among the frontrunners tomorrow that would be great.

“It suits our car better the cold; Spa was cold and Silverstone was cold.”

However, he concedes the Las Vegas street circuit is a very different circuit to Spa or Silverstone where Hamilton won.

“But,” the Austrian added, “it’s not entirely high-speed here but there are a few traction-limited slow corners. This will be key for us to manage that.”

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