The 2007 Apertura Tournament was Vidal's last with Colo-Colo as he left for Bayer Leverkusen in the summer. Bayer had tracked his progress for some time and his good showing at the U-20 World Cup that year convinced Bayer Leverkusen director of football Rudi Völler to make the trip to Chile to convince the 20-year-old to sign. The two clubs then agreed on a fee of US$11 million with Bayer Leverkusen, paying $7.7 million for 70% ownership of his contract. His transfer broke the previous national record of Matías Fernández's $9 million transfer to Villarreal.