Red Bull team boss Christian Horner has accused rivals Mercedes of applying pressure "tantamount to bullying" that led to the removal of Formula 1 Race Director Michael Masi.
Masi was removed over the winter by new FIA President Mohammed Bin Sulayem following the controversial events of the 2021 Abu Dhabi Grand Prix.
That event saw the sport plunge into controversy after Max Verstappen snatched the world title away from Lewis Hamilton.
In the eyes of Horner, Masi was removed due to the pressure applied on the FIA by Mercedes, unhappy with a number of crucial decisions made by the Australian during the final race.
Horner has compared that pressure to "bullying", describing Mercedes' behaviour as "unfair".
Horner: It was wrong to fire Masi amid Mercedes pressure
"Was it right to fire him based on pressure that was placed on him from a rival team? That for me was wrong," Horner said, speaking to BBC Sport.
"That's tantamount to bullying. It's passively aggressive.
"Yes, Michael did make mistakes and it was frustrating, but you have to look at the role that he was in and the tools that he had at his disposal.
"You can't just place the blame on Michael. It's unfair to do that."
He added: "We were on the receiving end of many of Michael's errors. But he is in a high-pressure role in a high-pressure sport."
Abuse aimed at Masi over the winter was "unforgivable"
"What is unforgivable is the trolling, the abuse online, the death threats that he and his family had. That absolutely cannot be condoned in any way," Horner continued.
"That has nothing to do with the sport. It's just out-and-out bullying and I would not accept that in any way within our organisation.
"That's why I spoke up for Michael because I felt that he had not had any support, he had not had any backing. That he had been hung out to dry and that there was this concerted campaign that was very passive-aggressively focused against him.
"I will always stand up for someone who is being bullied. Bullying is not acceptable."
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