Trulli: 'Leaving Ferrari the biggest mistake of Alonso's career'

Jarno Trulli believes Fernando Alonso's Formula One career never improved after leaving Ferrari in 2014.

McLaren driver Fernando Alonso

Fernando Alonso made the biggest mistake of his Formula One career when he left Ferrari in 2014, according to former team-mate Jarno Trulli.

Two-time world champion Alonso moved to Ferrari in 2010 and finished second in the drivers' championship on three occasions – losing out to the Red Bull of Sebastian Vettel each time.

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His five-year stay with the Italian team ended badly, though, as the team struggled to be competitive in 2014, Alonso finishing sixth in the standings and failing to win a single race.

Rather than remain with the team, the Spaniard opted to return to McLaren – where he spent the 2007 season alongside Lewis Hamilton – but the team failed to provide him with a strong car.

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And Trulli – who partnered Alonso at Renault – says the decision to leave Ferrari was a poor career choice.

"Fernando is a strong character," the Italian told Omnisport.

"Inside the team he's not easy to handle, because of this he's probably taken some difficult decisions which caused eventually a step back when he left Ferrari.

"In his position I would have never left Ferrari, saying that he was tired of being second. I would have been more than happy to be second every year and try and fight for the championship for the rest of my life with Ferrari.

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"But this is unfortunately the way he is and the people who know him appreciate him both ways but sometimes Formula One is cruel.

"If you are not well behaved sometimes you can be pushed off from the team and unfortunately this is what happened with Fernando. He left Ferrari, he had no choices around because these days in Formula One the competitive cars are very limited compared to years before. 

"[He] went to McLaren hoping that McLaren would go back to the glorious times but McLaren has been struggling a lot and the other mistake was to blame Honda while the engine has been proved that it was not the only problem there.

"That was the biggest mistake of his career. Fernando always thought he was enough to win the championship, but unfortunately in Formula One the driver is never enough. You need a good car, you need good ones around you. Maybe this cost him a lot."