Drafted in the second round (54th overall) of the 1991 NFL Draft from Division II powerhouse North Dakota State, Phil Hansen made his way to Western New York as a determined and unassuming defensive end. Throughout his 11-season NFL journey, Hansen grew into a quiet hero of Buffalo's defense, constantly fighting to contain the run with fierce determination and pairing up with Bruce Smith to challenge opposing offensive lines.

Hansen demonstrated optimal length, leverage, and an unwavering motor at the defensive end position. Predominantly operating on the left side, he excelled in establishing a firm boundary against the run, employing a powerful bull-rush to collapse the pocket, thereby enabling linebackers to execute plays in open space. Although he seldom garnered national headlines, his exemplary technique against double-teams and persistent second-effort rushes rendered him an essential component of Buffalo's defensive strategies.

Hansen distinguished himself as a rookie in 1991, starting in 10 games and receiving PFWA All-Rookie Team honors as the Buffalo Bills advanced to their second consecutive AFC Championship. He rapidly became a regular starter, playing a crucial role on the offensive line during the team's postseason campaigns to Super Bowl XXVII and Super Bowl XXVIII.

One of his defining postseason moments came in the 1992 AFC Championship Game against Miami, when he made a crucial interception off Dan Marino, helping seal a 29–10 victory and sending Buffalo to its third consecutive Super Bowl. Hansen reached a personal peak in 1995, recording a career-high 10.0 sacks, followed by a career-best 132 tackles in 1996.

After the 2001 season, Hansen retired from professional football, having spent 11 years in Western New York and playing exclusively for the Bills. In 2011, the franchise honored his enduring contributions by inducting him into the Buffalo Bills Wall of Fame.