Red Bull boss Christian Horner says it is “enormously unlikely” that Sebastian Vettel will rejoin the team for the 2021 Formula 1 season.

Vettel, who will be leaving Ferrari when his contract expires at the end of this year, has blown the 2021 driver market wide open.

Current McLaren driver Carlos Sainz is set to be announced as his replacement, possibly as early as Thursday, while Vettel’s own future remains unclear as to whether he will remain in F1 or retire from the sport altogether.

Why is Sebastian Vettel leaving Ferrari? |

But a revival of the successful partnership that saw Vettel claim four successive world titles between 2010 and 2013 has all but been ruled out by Red Bull’s team principal.

Horner said a scenario of having “two alphas” within Red Bull’s driver line-up would not be “conducive” and insisted the team is happy with its current pairing of Max Verstappen, who earlier this year signed a new contract until the end of 2023, and youngster Alex Albon.

“It’s enormously unlikely,” Horner replied when asked about the development by Sky Sports News.

"We have a long-term agreement with Max [Verstappen], and I think Alex [Albon] is doing a good job.

"We've got a good dynamic within the team and experience shows that two alpha males doesn't tend to pan out well.

"Sebastian is still a very competitive grand prix driver so I don't think it would be conducive for our team to have two alphas. We're happy with the driver line-up we have.

“I'm sure he's not short of options moving forward, but obviously he's chosen it hasn't worked out for him at Ferrari.”

Vettel has been linked with a drop into F1’s midfield at either McLaren or Renault, with a driver shake-up throughout the grid likely as a direct result of his Ferrari exit.

And Horner believes Vettel will think “long an hard” before making any decision about his future.

"He's a guy of principles, I'm sure he's thought long and hard about it, and you have to respect his decision,” he explained.

"Where he goes to from here, I have no idea. But, as I say, he's a guy with great integrity, great principles and whether he chooses to continue or not he's achieved obviously a huge amount in his time in Formula 1.

"Four world championships, he's one of the most successful drivers of all time.

"He's still relatively young, he's in his early 30s, if he chose to stay he's obviously still very competitive.

"That's entirely down to him and nobody will know that other than Sebastian what his choices are. He's got strong values, he's got strong integrity, and I think he'll have thought long and hard about this."

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