Since Rosberg announced his retirement in Vienna on Friday, there has been a growing list of candidates mentioned as potential team-mate to Lewis Hamilton next year.

Mercedes motorsport boss Toto Wolff has declared that the team is looking at “all the options”, which range from promoting a young driver like Pascal Wehrlein to buying out the contract of one of the top drivers, all of whom are signed for 2017.

“We have lost a champion, the best driver of 2016,” Lauda, who serves as Mercedes non-executive chairman, is quoted as saying to Gazzetta dello Sport. “It won’t be easy to replace him because all the drivers of a certain standard have contracts with other teams.

“Taking a young driver is a risk, we don’t know if he will be strong. Practically half of the grid have offered themselves.”

Never afraid to speak his mind, Lauda also admitted that he and several team members took Rosberg’s decision “badly”.

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“I didn’t expect it, nobody in Mercedes imagined that he had had enough,” the former triple world champion added.

“At first I didn’t believe it. ‘Nico, what you told us, are you kidding by any chance? It’s a joke?’ But he said it was all true. Quite incredible.

“Rosberg’s decision has left us disorientated and unprepared, and all those who contributed to Nico winning the world title took it very badly.”

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