[5] Despite the accolades, Bergey's southern schoolmates would physically fight with the "Yankee" from western New York, and his actual time at ASU in Jonesboro was difficult.

The Bengals made the postseason that year, losing to the Baltimore Colts in the divisional round 17–0,[13] but Bergey did not record a statistic.

[8] Bergey signed a personal service contract on April 17, 1974, with the Washington Capitols, the owner of the World Football League (WFL)'s Virginia Ambassadors, which would later become the Florida Blazers once the circuit began play in July of that year.

However, the Bengals filed suit against Bergey for breach of contract and a temporary restraining order against the WFL and its franchises two days later on April 19.

In the hearing, which began on April 29 and was adjudicated 15 days later on May 14, the court concluded that Bergey had not breached his contract and the Bengals' motion for a temporary injunction was denied.

[16] He was traded from the Bengals to the Philadelphia Eagles for a 1977 first-round selection, Wilson Whitley, and first- and second-round picks in 1978, Ross Browner and Ray Griffin respectively, on July 10, 1974.

[20] Bergey played a key role in the Eagles' subsequent rise, culminating in the trip to Super Bowl XV.

His ability level was reduced by the injury (he evaluated it at 65%), and he could no longer reach runners in time to make the play; but he was still named All NFC by the Sporting News and went to the Super Bowl.

[26][8] He finished his career with 27 interceptions that he returned for 397 yards, 16 unofficial sacks (beginning in 1970), and 21 fumble recoveries.

[8] Bergey had conflicts with guard Conrad Dobler of the Eagles' NFC East rival St. Louis Cardinals, who once spit on him while he was downed and injured.

[31] The same year, the Philadelphia Sports Writers Association recognized Bergey with its Living Legend Award.

[21] Bergey was a plaintiff in the concussion related lawsuit against the NFL filed and settled in a Philadelphia federal court.

[37] In the film Silver Linings Playbook, Robert De Niro's character Pat Solitano Sr., an Eagles fanatic, wears a number 66 Bill Bergey jersey.

[38] Bergey was diagnosed with oral cancer in 2021 and determinedly fought in response to the disease, finding encouragement and inspiration from others, including former Buffalo Bills quarterback Jim Kelly.

[39] In October 2024, Bergey was among 60 former players under consideration for the 2025 Pro Football Hall of Fame class in the Senior category,[40] though he did not make it to the next round of 31 candidates.