Prior to his junior year of high school, Sanchez transferred to Mission Viejo, where Johnson, who was recognized as a "quarterback guru", having trained professionals like Carson Palmer, was head coach. Under Johnson's tutelage, Mark felt he would have a better opportunity to become a better player. Johnson tutored Mark on the complexities of the position and in two seasons with the team, Mark led the Diablos to a 27–1 record culminating with the California Interscholastic Federation Division II championship in 2004.