Lewis Hamilton says Ferrari have lost some of their straight-line dominance at the United States Grand Prix.
Valtteri Bottas took pole position at the Circuit of the Americas on Saturday, beating Sebastian Vettel into second to end a run of Ferrari qualifying successes that encompassed the six races since the summer break.
It was the longest run of single-team qualifying success since a run of 18 Mercedes poles spanning the 2016 and 2017 seasons.
Although Hamilton could only go fifth fastest, having abandoned his second Q3 lap, behind both Vettel and fourth-placed Charles Leclerc, he reported a thought-provoking trend.
"What's come out this week has been quite interesting to see," said Hamilton.
"I think they've lost a bit of power. I'm interested to see how that continues and how it reflects in the race.
"They're still quite quicker than us generally in the straights. Hopefully our car will be strong throughout the race."
The FIA has recently issued a technical directive regarding a fuel-flow process proposed by Red Bull, thought to be an attempt to try and find where Ferrari's recent advantage has come from.
The process was ruled illegal, but Mercedes boss Toto Wolff says it does not necessarily link to Ferrari's sudden drop-off in Austin.
He said: "Certainly the three teams were much closer together in terms of straight line performance here in the US, but I wouldn't say this is down to any specific event.
"It's just a fact that we've won our first pole position since July, since Hockenheim, and we were really in the mix.
"I think it's very strong that the FIA issued a TD clarifying the situation, with some very clear wording.
"But this is a process that is standard, it's happened before, and part of the role of the governing body."
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