He played his entire career for the Giants and won two Super Bowl Championship and two NFC Championships in 2007 and 2011. In 2008 Diehl was named a Second-team All-Pro, and in 2009 he made it to the Pro Bowl. In 2008 he signed a six year deal with the Giants worth $31 million. The Giants announced that he would have surgery on his right thumb in August 2013. In January 2014 Diehl announced that he would be retiring after playing 11 seasons for the Giants. In August 2014 David became part of the Fox NFL team as a color analyst. He received the Wellington Mara NFL Man of the Year Award in 2012.