Russ Brandon, the longtime president of both the Buffalo Bills and Buffalo Sabres, resigned on Tuesday.
Terry and Kim Pegula, who are the owners of Pegula Sports and Entertainment which owns both teams, accepted the resignation.
Brandon has been with the Bills in various roles since 1997. He was made president in 2013.
He has been president of the Sabres since 2015.
Kim Pegula will take over Brandon's roles, with her husband continuing to oversee both teams' operations.
"We have a tremendous amount of confidence in the strong leadership teams we have built within each of those entities over the last several years," the Pegulas said in a statement.