Mercedes boss Toto Wolff declares the German team had doubts over whether Lewis Hamilton would be able to perform in 2018 due to his hectic schedule.
In a season which saw the Brit win his fifth world championship, Hamilton tallied up more air miles than ever before. Promoting his own fashion range bulked up his diary, particularly ahead of the Singapore Grand Prix.
Hamilton made appearances in New York and China before stepping foot in the Silver Arrow. Wolff confirms the team were concerned about his ability to perform until he smashed his qualifying lap.
"We always have to wait and see how Lewis feels about it. He flew to Shanghai and then to New York prior to the Singapore Grand Prix, but to be honest, we did have our doubts about it," Wolff told Formule 1.
"When he put in that mega lap in qualifying, I knew enough."