Max Verstappen stormed to pole position by over two-tenths ahead of Lewis Hamilton, while Bottas had to settle for fourth - he will be forced to start from ninth after taking a sixth ICE component which resulted in a five-place grid penalty.

Mercedes was in a league of its own in first practice on Friday as Bottas led the way ahead of Hamilton, with Verstappen a substantial nine-tenths off the pace.

Assessing Mercedes' competitiveness in Austin, Bottas says that Red Bull did a better job overnight.

“Yesterday they looked OK, but nothing amazing, so they found more than we did overnight,” Bottas said after qualifying. “For me the car felt a lot better than it did yesterday, but Red Bull made a bigger step with performance and they definitively had the upper hand today.

“I still think that race pace-wise it will be quite similar.”

Even though Mercedes has historically struggled in warmer temperatures, Bottas doesn’t think that’s the reason why Red Bull had the quicker car in qualifying at the Circuit of the Americas.

“No, I don’t think we got hurt much by that, I don’t think there were issues with that,” Bottas added. “Even the bodywork, cooling wise, wasn’t that penalizing. Maybe it was set-up wise that Red Bull found more.”

Mercedes’ technical director James Allison concurred with Bottas’ assessment that Red Bull had made sizeable gains throughout the three practice sessions, while the reigning world champions were forced to “migrate” back to the car setup it started the weekend with.

“Well, I guess we had reasonably high hopes after FP1,” Allison said. “FP2 was a bit more of a struggle and it’s a little bit that way since. We’ve been up at the sharp end but not really with the edge that we’ve seen in some of the recent races. Not been easy.

“We were running in qualifying very similar setups to where we started in FP1 having migrated a bit in-between. Probably a bit more of Red Bull having a stronger weekend of development than we did.”