He played college football for the Stanford Cardinal and was selected by the 49ers in the seventh round (239th overall) of the 2002 NFL draft.

Heitmann became the first Stanford offensive lineman voted All-American since Bob Whitfield in 1992.

Prior to the 2005 season, he worked to get stronger and more powerful under the tutelage of renowned strength coach Johnny Parker.

However, on December 14, in a game against the Seattle Seahawks, Heitmann broke his right tibia with 6:13 left in the first quarter on a two-yard run by Frank Gore.

For his dedication and commitment, Heitmann was given the Bobb McKittrick award, named after the late 49ers offensive line coach.