Sebastian Vettel dominates practice at United States Grand Prix . Teammate Mark Webber of Australia was second quickest with Alonso third ahead of the McLaren pair of Lewis Hamilton and Jenson Button . F1 championship leader fastest in both morning and afternoon sessions . The first day of the U.S. GP was dominated by Sebastian Vettel, who won his second race on a circuit he has never previously raced on. Nearest challenger Fernando Alonso third fastest for Ferrari in second runs .
Sebastian Vettel dominates practice at United States Grand Prix . F1 championship leader fastest in both morning and afternoon sessions . The first day of the U.S. GP was dominated by Sebastian Vettel, who won his second race on a circuit he has never previously raced on. Nearest challenger Fernando Alonso third fastest for Ferrari in second runs .