He played college football for the Arizona State Sun Devils, and was selected by the 49ers in the seventh round of the 2000 NFL draft.

At Red Mountain High School in Mesa, he lettered in football, basketball, and track.

Jennings played his entire career as the starting long snapper for the San Francisco 49ers, a role he filled for the team for thirteen seasons.

In 2003, Jennings signed an offer sheet as a restricted free agent with the Detroit Lions.

[8] Jennings is a regular on KNBR radio, due to his lively personality and intelligently comedic commentary.