Hamilton began his car racing career in the 2001 British Formula Renault Winter Series, finishing fifth in the standings. This led to a full 2002 Formula Renault UK campaign with Manor Motorsport in which he finished third overall. He remained with Manor for another year, winning the championship ahead of Alex Lloyd. Having clinched the championship, Hamilton missed the last two races of the season to make his debut in the season finale of the British Formula 3 Championship. In his first race he was forced out with a puncture, and in the second he crashed out and was taken to hospital after a collision with teammate Tor Graves.