FERNANDO Alonso would have been Nico Rosberg’s preferred option to partner Lewis Hamilton at Mercedes.

Rosberg, the defending Formula One champion, retired five days after winning the title to leave a vacant seat at the all-conquering team.

Alonso, who is under contract with McLaren until the end of the year, had been mooted as a mouth-watering candidate to replace Rosberg before Mercedes moved to hire Valtteri Bottas from Williams.

Hamilton partnered Alonso at McLaren in his very first season in the sport, but endured a fractious relationship with the Spaniard who ended up quitting the team.

“OK, because I’m now a fan, and on that side of the fence, it’s very easy to respond,” said Rosberg when asked who he would have preferred to replace him at Mercedes.

“Everyone says Alonso and I say it too, because there would be fireworks with Hamilton. As a fan, it would be nice, but for the team, it wouldn’t work.

“They’ve found a great solution. Bottas is fast and though Hamilton will be at a very, very high level and it will be difficult to beat him. I have proved that he can.”

Rosberg, 31, stunned the world of sport after retiring in the aftermath of his title triumph at the season-ending race in Abu Dhabi.

He will take on a role as a Mercedes ambassador this season and intends to attend some of the races.

But his association with the sport will be remembered for his fierce rivalry with Hamilton in the three years in which they fought directly for the title.

“It is much more complicated to fight for the title with your own partner,” added Rosberg, who was speaking to Spanish newspaper Marca. “It’s happened very rarely and complicates everything.

“You both have to drive for your team but at the same time think about winning, and finding the right balance is very difficult. I have always been treated very well on the team, but it was complicated.

“When Hamilton arrived I had been in the team for three years, but he came as a world champion and so it was normal for people to pay more respect to him than me, and listen more to what he said. They were difficult moments to begin with, but I also got respect in the end.”

Niki Lauda, the Mercedes’ non-executive chairman, has been critical of Rosberg’s decision to retire, but the German added: “I’ve calculated that 85 per cent of the people applauded me for the decision to finish when I was at the top.

“With Lauda it has been more complicated and though he seems angry in the press, with me he isn’t.”