David Diehl is a retired American football player that has an estimated net worth of $13.6 million. David Diehl began his career during his school years in the University of Illinois at Urbana-Champaign. He played with the Illinois Fighting Illini football team, and became a second-team All-Big Ten Conference selection in 2002. He was the selected by the New York Giants during the 2003 NFL Draft. After 11 seasons with all the Giants, he declared his retirement on January 24, 2014.