Christian Horner has admitted that he decided to apply 'pressure' on former Formula 1 race director Michael Masi, in the controversial ending to the 2021 season, leading to Max Verstappen beating Lewis Hamilton to the drivers' championship.

Hamilton was cruising towards his eighth drivers' championship at the Abu Dhabi Grand Prix, before Nicholas Latifi slammed into the wall and brought out the safety car. Initially, teams were told that no cars would be allowed to un-lap themselves.

However, with the track then clear, Masi allowed the five lapped cars between Hamilton and Verstappen to unlap themselves. This led to a one-lap sprint, where Verstappen, on fresher tyres after pitting behind the safety car, was able to pass Hamilton to win his first championship.

Horner reveals pressure on Masi

Horner, in his memoir 'Drive', revealed his 'heart sank' when the instructions initially arrived for the lapped cars would not be able to unlap themselves, with five backmarker separating Hamilton and Verstappen in second.

He said: "That meant that Max would have to pass all five cars before getting to Lewis, which was impossible in one racing lap. The Abu Dhabi Grand Prix, and by extension an entire season, was being concluded in the most unsatisfying manner. I couldn’t understand the decision.

"The watching world wanted to see Max and Lewis go head to head in a title decider, not crawl to an underwhelming finish. Anything else was a disappointment."

"I decided to apply some more pressure on race control. ‘Come on, Michael, we need to get this race going; why aren’t we getting these lapped cars out the way?’ I said. ‘It’ll be such a shame to end everything under a safety. The lapped cars should unlap. Let’s race.’"

Horner has made a number of admissions in his autobiography, including on how he wanted to sign Charles Leclerc and Fernando Alonso for Red Bull, and how he believes Liam Lawson should never have been promoted.