premise: Sebastian Vettel works for Red Bull as a race car driver.
hypothesis: Sebastian Vettel ( [ zeˈbasti̯an ˈfɛtl̩ ] ; born 3 July 1987 ) is a German racing driver currently driving in Formula One for Scuderia Ferrari . He is a four-time Formula One World Champion , having won the championship in , , and with Red Bull Racing . Vettel started his career in Formula One as a test driver for BMW Sauber and made his debut with the team at the 2007 United States Grand Prix , replacing the injured Robert Kubica . In his first year driving for Red Bull in , Vettel finished the season as the youngest-ever World Drivers ' Championship runner-up . Vettel left Red Bull Racing and ended his long-term association with the company after the season and signed a contract with Ferrari for , after activating a clause to terminate his Red Bull contract early .