Mercedes team principal Toto Wolff has played down the suggestion his team is about to embark on another period of dominance in Formula 1, and believes the battle for the 2027 title has already started.

They sealed the constructors' championship with three races of the season remaining at the Sao Paulo Grand Prix on Sunday, just one week after Kimi Antonelli secured the drivers' championship in Mexico City.

The German manufacturer stole a march on its rivals at the start of the year following the introduction of new engine regulations and has continued to be competitive throughout the season.

But after winning just one race in the last five, Wolff believes rival teams Red Bull, McLaren and Ferrari are in a position to pose a serious threat for the title in 2027.

"Look at the last few races, we haven't won," Wolff said. "And today at the beginning of the race, Kimi was just storming away, it looked like this could be ours, but the competition has been getting tougher, between Ferrari, McLaren, Red Bull and ourselves.

"It's four teams that can win races and will be challenging for a world championship. And I have no doubt that it's going to be very difficult for us next year.

"So for me, the 2027 season has started now. It is about learning in the three last races.

"What is it we can optimise? What didn't we spot when we put the upgrade on the car? What is it we can learn from today, and attack these last three races full blast, whilst also making sure that we have the learning for next year's power unit and next year's car."

Wolff believes the sheer quality of the top teams on the grid means the era of runaway teams in new regulations cycles -- such as Mercedes from 2014 and Red Bull from 2022 -- is a thing of the past.

"It looks like the most competitive era that is about to start, because the teams have become so professional in capability, in resource, that these kind of runaway seasons, I don't see them anymore, whether it's four in a row or eight in a row," he said. "And that is a completely new challenge.

"You can see how quickly it goes from being dominant and within a few races you realise that your upgrade doesn't work and you fall back and you're just third on the road. So it's great for the sport.

"I wish it was the era of Mercedes and me running away with another few titles, but I don't think it's the reality."

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Wolff believes one of the keys to Mercedes' success remains its no-blame culture and its ability to empower its employees.

"We have stability certainly as a factor, but we have also many people that have joined us recently, and I think what I would like to choose as a word is safety. We are not a high-and-fire organisation.

"We provide a culture and an environment where you can thrive, where you are allowed to make mistakes, where you can speak up. And over the long term, I believe, if you want to be successful, not over a period of a few years, but over many decades, this is what you need to be able to kind of ingrain in the team. And we're trying that.

"It's not something you put on a PowerPoint. You have to live those standards in and out. These are the standards we are setting for ourselves.

"Sometimes we fail, but we look at the long-term vision. For me, soon is in ten years, and I need to set the team up for soon."