Heading into this weekend's Korean Grand Prix, the Formula One drivers' championship is shaping up as a duel between defending champion Sebastian Vettel of Red Bull and leader Fernando Alonso of Ferrari.
Vettel took his second consecutive checkered flag at the Japanese GP on Sunday to move within four points of Alonso with five races left. Alonso's lead was further eroded after he crashed on the first turn in Suzuka.
Vettel's dominating win from the pole at Suzuka made him the first driver this season to record back-to-back victories, and he joined Alonso and Mercedes-bound Lewis Hamilton as the only drivers to win three times this season.
Despite his recent success, Vettel said a lot of things can change between now and the end of the season.
''Things can change very quickly,'' said Vettel, who also won last year's Korean GP. ''It's much closer now but every weekend can be different. It's a very new calendar for all of us this year with back-to-back races in Japan and Korea and...