Pegula said McDermott took a more active role in draft decisions over the weekend, including the Bills moving out of their original first-round slot -- No. 10 -- in a trade with the Kansas City Chiefs.
"After a thorough review of our football operations over the past several months, Kim and I informed Doug this morning that we will be moving in a new direction," Terry Pegula said Sunday in a statement. " We have enjoyed working with Doug. He is a good person and we want to thank him for his work and commitment to our football team. This was my decision. It was not an easy decision but I believe it's the right one for the future of the Buffalo Bills. Our search for a new general manager will begin immediately."
Whaley and Ryan were not on the same page when 2016 came to a close.
The Bills went 30-34 during Whaley's four-year run as general manager.
Among candidates the Bills could consider are recently fired Colts general manager Ryan Grigson. Grigson and McDermott worked with the Eagles 10 years ago and are film and football junkies with a strong bond.