Harrison, who played quarterback for one season at the University of Hawaii, spent the 2001 season at Cerritos College in Norwalk, Calif., where he set three school records. In 2001, Harrison set school records for attempts (293), completions (145) and total plays (340).
A 6-foot-2, 210-pounder, Harrison threw for 1,847 yards and 17 touchdowns in the 2001 season for Cerritos, leading the Falcons to a 7-4 mark.
Harrison was a starter at Hawaii in his true freshman season and played in five games, but he received a redshirt in his second year with the Rainbow Warriors. As a freshman, he completed 9-of-20 passes for 91 yards and one interception. He also scored a touchdown on a 14-yard run against the University of Texas-El Paso.
At Mayfair High School, Harrison passed for 2,900 yards and 31 touchdowns as a senior. He was named the CIF Division IX Offensive Most Valuable Player and was the Suburban League MVP.
Harrison joins an LSU team that was a quarterback short after losing Marcus Randall to a torn ACL in the Tigers' spring game.