There is nothing quite like a potential title decider to bring the fiercest of spotlights to bear as doubtless Kimi Antonelli will discover when he attempts to seal his first championship at the United States Grand Prix this weekend.

For the young Italian the goal is straightforward and the culmination of a childhood dream. However, for his Mercedes team there will be scrutiny over performance in Austin that has significant implications going into next season.

The 20-year-old Antonelli holds a 102-point lead over his teammate George Russell and will become Formula One’s youngest world champion if he wins, Russell finishes ninth or lower and Ferrari’s Lewis Hamilton is fifth or lower. It is not an entirely impossible scenario but even if he does not clinch the title in Texas, in all likelihood he will be crowned in Mexico a week later.

Antonelli has been exceptional in only his second season in F1, but also enjoyed what was for the opening half of the season an all but untouchable car. Mercedes can no longer boast that advantage. Max Verstappen has won the past two races as Red Bull’s upgrades finally unlocked the performance they felt was there to be exploited.

Ferrari, too, are now close to Mercedes, capable of beating them and have a raft of aerodynamic upgrades arriving in Austin. McLaren, having dropped back a tad in recent races, have repeatedly proved to have the measure of the championship leaders and have upgrades planned for the coming triple-header in the US, Mexico and Brazil.

Mercedes had not had it all quite their own way then when they brought their second and final improvements to the Bahrain Grand Prix in Malaysia. Yet an expected uplift of as much as three-10ths a lap was met with disappointment. The upgrades did not deliver as expected and the car became a handful to drive, gains in lap time unsurprisingly elusive.

The Mercedes is less forgiving, switching between understeer and oversteer in a narrow window, working the tyres harder.

Such was the discrepancy between what occurred on track and what was expected that after Malaysia they reverted to using the old spec on Russell’s car and the new one on Antonelli’s to better assess the issues at the following Singapore GP, after which the Italian felt there had been an improvement.

All of which is part of the development process, especially in a season of new regulations but as the Mercedes team principal Toto Wolff noted, these updates were not only intended to enhance and improve but were of paramount importance because they would inform next season’s car.

“Was it an easy car like the previous one? I don’t think it was. Does it have the performance that we were hoping the upgrade would bring? I don’t think so yet. But it was a step in the right direction,” Wolff said after Singapore. “In Austin, we should see whether we can continue to consolidate that and whether it has more performance, because it’s crucial for the development direction for the next year.”

While Malaysia and Singapore might be considered outliers, Austin is a typical circuit, with medium and fast speed corners on a flowing track where good balance and a quick, well-behaving car is rewarded – the type of track where Mercedes were in control for the much of the season.

That said, some at the team may be forgiven for experiencing a discomforting sense of deja vu. In each of the previous four years, with many upgrades not delivering as expected and in some cases setting the team back.

To be fair, Mercedes are far from such straits now and are still quick. Yet they have nowhere near the level of dominance they enjoyed in the 2014-2020 period when they remained all but untouchable and missteps along the way were almost unheard of.

At the time the opposition closed on them but in most cases that was because Mercedes was already switching resources to the following year, confident they were ahead of the game and in where they needed to go with next year’s model.

As this season draws to a close there is no such clear-cut advantage. The front runners are all still feeling their way toward exploiting the maximum from the new regulations. The direction for 2027 is vital because the field is far more closely matched and developing at a fearsome rate, as Red Bull have demonstrated.

Mercedes’ lead this season is nonetheless formidable and while they cannot seal the constructors’ championship this weekend, Antonelli’s drivers’ title is surely all but done and dusted. Austin, however, might yet suggest whether they can repeat the feat in 2027.