Max Verstappen would have retained the Formula One drivers' championship had Red Bull removed team principal Christian Horner earlier in the season.

That is the view of outgoing team advisor Helmut Marko, who announced last week that he will not return for 2026 following a 20-year stint with the team.

Horner had also spent two decades as Red Bull's team principal and chief executive, but he was dismissed in July after a difficult start to the season.

Horner was accused of sexual harassment and controlling behaviour by a female employee last year, with an internal investigation and a subsequent appeal both seeing him cleared.

It was also suggested that Horner's relationship with four-time world champion Verstappen had deteriorated to the point that the Dutchman was considering a move to Mercedes.

At the time of Horner's departure, Marko said the decision was strictly performance-related. Verstappen had only won two of the season's first 12 races by that point, though he won six of 12 from then on.

Those six victories all arrived in the final nine weeks of the campaign and saw him narrowly miss out on a record-equalling fifth consecutive world title, finishing two points behind McLaren's Lando Norris.

And Marko feels Horner's presence contributed to Red Bull's slow start to 2025, telling Dutch publication De Limburger: "We had to act because performance on track was falling behind.

"And if we had done it earlier, we would have got things back on track sooner and Max Verstappen would have been world champion this year. I am absolutely convinced of that."

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Marko also accused Horner of planting negative stories about him in the press during their final few years working together, as he detailed the strained nature of their relationship.

"Those final years with Horner were not pleasant," he added. "Dirty games were being played.

"Do you remember when it was claimed that I said Mexicans were less focused than Dutch or German people during Sergio Perez's time? That was fabricated – possibly by them.

"The same goes for the claim that in 2024 I spread the story that our engine development was behind schedule and that we would therefore lose Ford as a partner.

"I never said that, but Horner wanted to use it to have me suspended. Because of Max's support, that didn't happen."