DiGiorgio had a big year for the Bills in 2007. He played in all 16 games—the final 13 as a starter at middle linebacker—and was second on the team with 113 tackles. John took full advantage of Paul Posluszny's injury, and filled in as the middle linebacker in the 2007 season. As John filled in for the injured starting linebacker he did an exceptional job. His "blue-collar" work-ethics made him the 2007 Buffalo fan favorite. With Buffalo being a predominate blue-collared environment the fans took notice of John being a natural underdog in the NFL with a great work-ethic. The combination of hard-work and Buffalo natives recognizing his background, adversities, and doing an exceptional job as the backup MLB sparked the Buffalo fans support. He also had two fumble recoveries and an interception. The Bills were in the playoff hunt late in the season, but they lost their final three games to finish with a 7-9 record.