Ferrari have their rivals worried after a storming start to the Mexican GP weekend, with Lewis Hamilton claiming the pace-setters have a "massive" advantage and Max Verstappen insisting they are "miles ahead".
The Scuderia, described as "unbeatable" over one lap by Mercedes, will be looking for a sixth straight F1 2019 pole in Saturday's qualifying and their practice pace certainly suggested that was possible, with Sebastian Vettel topping the timesheets in the more representative second Friday session.
Although Max Verstappen was only a tenth behind the lead Ferrari in Mexico City, with Vettel's team-mate Charles Leclerc third, Mercedes could only manage fourth and fifth through Valtteri Bottas and Lewis Hamilton - with the championship leader almost a second off the pace.
Hamilton can seal a sixth drivers' title this weekend but needs to outscore team-mate Bottas by 14 points, and at the very least needs to finish on the podium. At this stage, the Englishman is struggling to see a way past Ferrari, who also unsurprisingly topped the speed traps on the long straight.
"It's not been a great day, but that is what it's usually been like for us here," said Hamilton, who has finished fourth and ninth in the last two races in Mexico.
"We've definitely learnt a lot. We've not particularly had any major dramas, it's just trying to understand these tyres. It was cool in the morning and then a bit warmer in P2, but from the short run to the long run it's hard to pinpoint exactly how you get these tyres working. But that's the name of the game.
P2: Vettel flying, Merc cut adrift
"I think we're not massively far off the Red Bulls but the Ferraris... they just keep turning up their engine down those straights. The difference between us and them is massive in a straight line, and I think between the rest of the drivers as well."
Valtteri Bottas, six tenths down in P2, admitted the gap to Ferrari was "bigger than we expected" - while Red Bull also believe Ferrari are the clear favourites heading into qualifying despite the slim gap between Verstappen and Vettel.
Verstappen believes Ferrari, who have regularly enjoyed a drastic improvement from Friday to Saturday of late, will be "just too quick" when it comes to the Q3 shootout.
"I don't think we can fight with them in qualifying," the Dutchman, looking for a hat-trick of Mexico wins, told Sky F1.
"The rest is pretty much in the same speed range but they are just miles ahead. That's the way it is at the moment and we just can't gain the time back in the corners unfortunately.
"I guess for us we need to focus more on the race, keep the tyres under control and then I think it can still be a good race."
Alex Albon crashed out of P2 in the sister Red Bull, losing valuable track time.
Vettel predicts 'tight' qualy; Mercedes 'not good enough'
Vettel, 0.4s in front of Leclerc on Friday afternoon, will be hoping to build on his Japanese GP pole in Mexico qualifying, and looked the most comfortable out on track to open the weekend.
But the German insisted the team still had plenty to improve, and added after practice: "It was very tight today, and I think it will be tomorrow with three teams."
Mercedes, however, are playing down Hamilton's chances of wrapping up the title this weekend.
"We knew [it would be tough to clinch it here]," team boss Toto Wolff told Sky F1. "I think we need to give a car that is reliable, that is the most important, and then fight it out on track.
"I don't think we have a good enough package this weekend to be at the very front, from a pure pace standpoint. But let's see. If we do it in Austin, we do it in Austin."
On their Friday pace, Wolff added: "Not good enough. We know this is a difficult track for us. We are just lacking the performance.
"I think it's one of our worst tracks. We had cold graining here last year and we are lacking real power this year in comparison to the others."
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