Taken second overall in the 1987 NFL Draft by Indianapolis out of Alabama, Cornelius Bennett landed in Buffalo following a blockbuster three-way trade before ever playing a down for the Colts. Joining a talent-rich core featuring Bruce Smith, Darryl Talley, and Shane Conlan, "Biscuit" brought rare, world-class athletic traits that elevated Ted Cottrell and Walt Corey's defense into an aggressive, championship-caliber unit.

Bennett possessed a rare combination of raw power, closing acceleration, and fluid movement skills. Operating as an outside linebacker in Buffalo's 3-4 front, he was equally adept at turning the corner as an explosive edge rusher or dropping back into pass coverage to blank out tight ends. His signature trait was his violent closing speed in pursuit—he possessed the lateral range to run down sweeps on the opposite sideline and the brute strength to blow up lead blockers in the hole.

Bennett made an immediate impact when he arrived midway through his rookie season in 1987, recording 8.5 sacks in just eight games. His rise to superstardom started in 1988. That year, he tallied 9.5 sacks, two interceptions, and three forced fumbles, earning him the UPI AFC Defensive Player of the Year award and his first Pro Bowl selection, along with a First-Team All-Pro honor.

As the Bills began their historic dominance in the early 1990s, Bennett was the driving force of Buffalo's front seven during four straight Super Bowl appearances (1990–1993). In 1991, he delivered another exceptional season, recording 78 tackles, 9.0 sacks, and three forced fumbles, earning his second UPI AFC Defensive Player of the Year award, his second First-Team All-Pro selection, and his third Pro Bowl.

He continued to be a dominant player throughout the decade, earning Pro Bowl selections in 1992, 1993, and 1995. His most memorable moment was during the 1993 playoffs against Oakland, when he delivered a powerful sack on Vince Evans, marking Buffalo's return to the championship game.

After nine stellar seasons in Western New York, salary-cap pressures led to a separation following the 1995 season. Bennett signed a free-agent deal with Atlanta in 1996, helping lead the Falcons to Super Bowl XXXIII before concluding his career with the Indianapolis Colts. His dominance throughout the era earned him a spot on the NFL 1990s All-Decade Team.

Bennett played in 128 regular-season games, accumulating 52.5 sacks, 793 total tackles, seven interceptions, 22 forced fumbles, and 19 fumble recoveries as a Bill. In 2010, the franchise honored his lasting impact by inducting Bennett into the Buffalo Bills Wall of Fame.