He holds the NCAADivision I (NCAA) record for most touchdown passes in a single season with 58. He holds several other NCAA Division I FBS records.
Early years
Brennan attended Mater Dei High School in California. He helped Mater Dei advance to the league championship in basketball as a senior. While at Mater Dei, he was the backup quarterback to Matt Leinart until Leinart graduated. After graduating from Mater Dei, Brennan attended Worcester Academy in Massachusetts for a postgraduate year, where his primary receivers were David Ball, now a wide receiver for the Erie Explosion of the Ultimate Indoor Football League, and Carl Elliott, the former starting point guard on George Washington's basketball team.