McLaren feared Fernando Alonso would quit on eve of 2017 season

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A new documentary has revealed McLaren had genuine fears Fernando Alonso would quit on the eve of the 2017 season and cause a domino effect which could destroy the team.

Amazon's 'Grand Prix Driver' follows the progress of McLaren during the early stages of 2017, when it started to realise the scale of the problems with Honda's engine. It was the third consecutive season the team was delivered an underpowered and unreliable power unit, ultimately leading to the split from Honda later in the year.

According to Motorsport.com the documentary, due for release on February 9, reveals just how worried McLaren bosses were that Alonso would have finally found the limits of his patience and simply decided to call it a day.

"After this testing, Fernando is quite pissed off," Boullier says to camera during the documentary. "He is clearly saying I may reconsider my position to race because I'm not going to survive another year like this.

"My main worry at this time is not to have the team collapsing. I know the domino effect as well, you know. I mean, in this business you know how it works...when you are weak, people they come, they just poach who they want. It takes years to build an F1 team but you can kill it in six months."

Boullier was so convinced Alonso would not be in the car for the Australian Grand Prix, he is shown telling McLaren COO Jonathan Neale shortly after the disastrous Barcelona tests: "He is going to say: 'You know what guys? Ciao bello'. He will not stay. I am a 100 percent certain he will not stay..."

The documentary goes on to reveal Alonso feared for his safety when driving the McLaren-Honda during the Barcelona sessions.

In radio broadcast especially for 'Grand Prix Driver', he is heard saying: "It's too dangerous to run like this. Horrible balance with the rear because the driveability was poor. So we cannot test like this."

"This is a really a [censored] engine. A [censored] power unit you know."

As it turned out, Alonso would stay -- a decision possibly helped by the sweetner offered to him by Zak Brown of missing the Monaco Grand Prix to contest his first Indy 500 later in the season. Several months later, Alonso would sign a deal to remain for 2018, something he put down to the team's switch from Honda to Renault power for the upcoming season.