LONDON, Dec 2 (Reuters) - Nico Rosberg stunned Formula One on Friday by announcing his retirement, only days after he had won the world championship with Mercedes at the season-ending Abu Dhabi Grand Prix.
The following details the reaction of those within the sport to his surprising decision:
Mercedes team boss Toto Wolff
"This is a brave decision by Nico and testament to the strength of his character," Wolff said in a team statement. "He has chosen to leave at the pinnacle of his career, as world champion, having achieved his childhood dream. The clarity of his judgement meant I accepted his decision straight away when he told me."
Team mate Lewis Hamilton
"This is the first time he's won (a title) in 18 years, hence why it was not a surprise that he decided to stop," the triple world champion told reporters ahead of the governing FIA's gala prize-giving in Vienna. He's also got a family to focus on, and wants more children, and Formula One takes so much of your time. Will I miss the rivalry? Of course."
FIA president Jean Todt
"I was privileged to receive a call from Toto Wolff this morning informing me of Nico's decision. I was very surprised, as I'm sure everyone is, but Nico has demonstrated across the year that he is extremely brave.
"I think he did five or six of the hardest laps of his life in the final race of the championship but the consequence is that he made it."
Former racer and Sky Sports F1 commentator Martin Brundle
"I find it absolutely extraordinary, a big surprise...it's obviously a personal decision and it's bad for Formula One because we haven't got a world champion through the winter and next season."
Olympic champion sprinter Usain Bolt
"I can't really understand it but everybody has their reasons, I guess he felt like he's got what he wanted," Bolt told reporters in Monaco ahead of the athlete of the year awards. "When you get where you want to be, if you accomplish your goal, I guess there's no reason to keep going."
Formula One drivers on Twitter
"Definitely a great Champion!!!! Big admiration" - Force India's Sergio Perez.
"Respect my friend! @nico_rosberg" - Haas's Romain Grosjean.
"Big respect" - Danish driver Kevin Magnussen
"Well done Nico. More to life than chasing round in circles. Respect" - 1996 champion Damon Hill
"Nico what a brave very brave decision, he has some very powerful reasons I am sure. Brilliant World Champion.Very interesting for Merc now." - 1992 champion Nigel Mansell.
Formula One supremo Bernie Ecclestone
"He needs more time to spend his money, that's all" (Reporting by Alan Baldwin, editing by Toby Davis)