Ferrari's Sebastian Vettel: I wasn't 'at top of my game' in F1 2018 - Autosport

Sebastian Vettel admits he was not "at the top of my game" in Formula 1 this season at times, but knows where he and Ferrari next to improve for 2019

Read more: Ferrari's Sebastian Vettel: I wasn't 'at top of my game' in F1 2018 - Autosport