Damon Hill has wondered whether it's a coincidence that Red Bull's competitiveness improved throughout the United States Grand Prix weekend, at the same time that Adrian Newey was back directly working with the team.
The legendary designer had missed a handful of races after a cycling accident during the summer, returning to work just before the Turkish Grand Prix where Red Bull struggled to unlock pace from their RB16B.
Red Bull finished first practice in Austin a second off the pace of Mercedes, but slowly ramped it up to clinch pole position on Saturday afternoon before claiming a hard-fought victory on Sunday.
Given the improvements Red Bull made over the course of the weekend, Hill questioned how much of it was down to Newey's return.
"I want to get to the bottom of how much influence Adrian had," Hill said on the F1 Nation podcast.
"Because Adrian had this little whoopsie here on his bicycle in the summer and he's been away from it a bit.
"But he was back there this weekend in Austin. Red Bull did not look on the pace on the first day, from the get go. Mercedes looked like they had an advantage.
"But they worked away and they got better and better. Some people feel that, in Turkey, Red Bull were just not optimising the car. And actually, it wasn't so much that Mercedes had found something, it was more that Red Bull had lost something, or not extracted the very best in the setup.
"They certainly got better and better over the weekend in Austin."
Red Bull team boss Christian Horner downplayed the importance of Newey's return over the United States GP weekend.
Speaking to media, including RacingNews365.com, Horner explained that he has been back working for the last two races.
"Obviously, things get blown out of proportion sometimes," he commented.
"He had an accident whilst on holiday. Thankfully, he's back fully fit, he has been three weeks now. So he was in Istanbul and here this weekend, and is in good shape."
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