Rosberg retires as F1's best driver, Mercedes boss Wolff says

After finishing second to Mercedes team-mate Lewis Hamilton in the 2014 and '15 title fights, Rosberg became world champion for the first time last Sunday in Abu Dhabi.

However, just five days after winning the 2016 title, Rosberg stunned motorsport by announcing his immediate retirement.

While Hamilton's unreliability during the season was a major point of discussion, Wolff said Rosberg's final achievement proves his worth.

"The results show he won the world championship," Wolff said.

"He is the best driver in Formula 1 today and the points show that.

"The way I've perceived the last few races was that he was extremely professional and he did what was needed.

"He had an incredible winning streak at the beginning of the season [four races] to build the foundation and he just drove it home."

Rosberg graduated to F1 as the reigning GP2 champion in 2006 with Williams, spending his first four seasons with the team.

When Mercedes returned as a works team in 2010 after buying Brawn GP, it recruited Rosberg and Michael Schumacher, who came out of retirement.

Rosberg won the first of his 23 grands prix in China in 2012 and two more in '13, before Mercedes stamped its dominance on the new turbo-hybrid era.

"He leaves a huge legacy," Wolff said.

"First of all the way he has chosen to leave Formula 1 is something that is unheard of.

"It is something that all of us admire in a certain way, calling it a day when you are the best and at the top.

"He has been part of the development of the team since the very early days and such a strong team member.

"The team has developed because the balance is right between the drivers and the dynamics within the team.

"The balance is very important and Nico was a big contributor."