|Ohio State Buckeyes No. 18|
|High school||Las Vegas (NV) Bishop Gorman|
|Date of birth||January 26, 1998|
|Place of birth||Poway, California|
|Height||5 ft 11 in (1.80 m)|
|Weight||203 lb (92 kg)|
|Career highlights and awards|
Martell attended Bishop Gorman High School in Las Vegas, Nevada. As a senior, he was the Gatorade Football Player of the Year after leading the team to a 15–0 record, while passing for 2,362 yards and 41 touchdowns, and rushing for 1,253 yards and 21 touchdowns. For his career, he went 45–0 as a starter and finished second in Nevada history with 7,510 passing yards and 113 touchdowns.
Martell was rated by Scout.com as a five-star recruit and was ranked as the second best quarterback and 26th best player overall in his class. He originally committed to the University of Washington when he was 14. In 2015 he changed his commitment to Texas A&M University. In May 2016 he decommitted from A&M and a month later committed to Ohio State University. Martell transferred to Desert Pines High School after his senior season, so that he could graduate and enroll at Ohio State early.