However, Sainz will start down in 12th after a loose drain cover destroyed his Ferrari in practice and triggered a 10-place grid penalty.
Triple world champion Max Verstappen, a winner in 17 of the 20 rounds so far, took third spot for Red Bull, but will move up to second following Sainz’s demotion. Lewis Hamilton was eliminated in Q2, leaving him only 10th on the grid.
Hamilton finished half-a-second behind team-mate George Russell, who hauled his Mercedes into Q3 before taking advantage of Sainz’s penalty to secure third on the grid for Saturday’s 50-lap race.
Following the shambolic start to F1’s Sin City comeback here on Thursday night, qualifying passed off without significant incident – much to the relief of the sport’s under-fire bosses.
F1 CEO Stefano Domenicali stopped short of issuing an apology to the furious spectators, who saw just eight minutes of practice before they were ejected from the stands.
However, in the early hours of Saturday morning, the estimated 90,000 fans who filled the 3.8-mile street venue – 30,000 down on capacity – were treated to an uninterrupted session which saw Leclerc romp to top spot in his scarlet machine.
“I am happy,” said Leclerc. “To have first place in Las Vegas is great.
“I was a bit disappointed because my lap was not great but it was all we needed. In the race we usually lack pace but hopefully we can put it all together in the race.”
A fortnight after the seven-time world champion finished eighth in Brazil – 63 seconds behind winner Verstappen – he struggled for pace in his underperforming Mercedes.
“Couldn’t go faster, mate,” said Hamilton following his elimination. Behind Hamilton, Sergio Perez qualified one place back.
But the British driver failed to make it out of Q2 with his McLaren machinery not suited to the three long straights here coupled with slow corners.
He qualified only 16th, three places ahead of team-mate Oscar Piastri who also fell at the first hurdle.
“Very disappointed,” said McLaren CEO Zak Brown. “We thought we’d struggle this weekend but I didn’t think either car would be out in Q1.
“Not a good start to the weekend and now all we can do is focus on the race tomorrow.”
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