Formula 1 championship leader Kimi Antonelli reckons his United States Grand Prix pole is the reward for Mercedes' efforts to finetune its comprehensive but troubled Malaysia upgrade.

Antonelli held off Red Bull tandem Max Verstappen and Isack Hadjar on Austin's Circuit of the Americas as Ferrari flattered to deceive in Saturday's qualifying shootout by taking fourth and fifth.

With the gusty conditions only getting worse throughout Q3, nailing the first of two qualifying runs proved to be pivotal. And following a weekend that had been building up as a battle between Verstappen and Ferrari duo Charles Leclerc plus Lewis Hamilton, Antonelli sprung somewhat of a surprise by taking his first pole since July's Belgian Grand Prix.

It was a reward for Mercedes' efforts to exploit its big Malaysia upgrade, which has made the W17 faster but also more difficult to set up. That struggle looked set to continue in Austin's first practice session, but the team gradually chipped away to improve the balance. A new front wing for Austin, which was trialled in Singapore practice, was intended to further improve the package.

"I'm happy because we've been working really hard on this package, and we're still trying to understand it fully," said Antonelli, after denying Verstappen a third consecutive pole.

"Since Singapore, we've taken a big step further, and now we've just got to keep working on it, keep understanding. But it's a good result for the team because they've done a tremendous job on bringing this package. Finally, we're seeing the results.

Andrea Kimi Antonelli, Mercedes

Photo by: Mark Sutton / Formula 1 via Getty Images

"It was surprising, but also one of the biggest achievements for me today is that I didn't do track limits! That also made our life a little bit easier. I didn't put myself in a difficult situation, and we were able to just progress throughout the session and build from there."

Antonelli gets a first, if remote, opportunity to tie up the championship on Sunday if he wins the race and team-mate George Russell finishes ninth or lower, and Hamilton is no higher than fifth.

With Hamilton and Russell only starting fifth and sixth respectively, the chances of Antonelli celebrating a maiden title in Texas may still be small, but they are not negligible either.

"I'm just going to try to do the best race I can. I'm going to try to win, and then we'll see what happens," said the 20-year-old Italian.

"It does feel a little bit different, but the goal stays the same. I just need to keep doing my job, and actually, I feel like I can enjoy the driving and everything more because I'm in a very good position. But still, the mindset is always the same."