Mazepin threatened to pull Uralkali funding from Haas in 2021

Uralkali chairman Dmitry Mazepin threatened to terminate the company's sponsorship of the Haas F1 outfit in 2021 if the team didn't switch chassis between his son Nikita and Mick Schumacher.

Early last season, Mazepin claimed that his underperformance relative to Schumacher was due to him racing a heavier car than his teammate, one that he claimed left him as a "sitting duck" among the laggards at the tail end of the field.

Haas team boss Guenther Steiner would later confirm that there was a slight weight difference between Mazepin and Schumacher's year-old VF-21 cars "depending on the weight distribution". But the Italian insisted at the time that the disparity was minimal.

However, it has been revealed in an early preview of the latest 'Drive to Survive' docuseries by Netflix that will be released next week that tensions had ramped up between Haas and the Mazepin camp, with father and son believing that they were being given a raw deal by the US outfit.

"It’s the same car," Steiner told Nikita Mazepin. "As much as you believe it’s not, it’s the same car."

Unconvinced, the young Russian's father stepped in and vowed to put the pressure on Haas.

In a scene filmed at the Spanish Grand Prix in Barcelona, Dmitry Mazepin vents his frustration to his son's advisor Jesper Carlsen

"If it doesn’t change, I will send an official letter that we stop financing and stop racing," he warned.

"It will be a huge problem with the money and they will decide what to do because we will not keep this ‘let’s do, let’s do, let’s try, let’s try.’

"We already tried [for] three races and if we remove the Uralkali, we stop racing. Switch the cars. Everybody knows that someone has an advantage."

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Carlsen duly informed Steiner of Mazepin's threat which he said was justified by his belief that "there's a difference between the cars".

Confronted with the Russian's warning, Steiner responds on camera and says: "I don’t want to go there on an interview."

Eventually, Nikita Mazepin received what he asked for, namely a lighter chassis that was supplied to him from the Belgian Grand Prix at Spa.

The young Russian subsequently claimed that the switch had "massively improved" his one-lap pace, although he only succeeded in outqualifying Schumacher once in the second half of the 2021 season.

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