Brooks spent the past five seasons as the Wizards' coach, taking Washington to the playoffs three times and advancing to the Eastern Conference semifinals in 2017.
But the Wizards announced last month that Brooks would not return, with general manager Tommy Sheppard saying it was his decision not to renew Brooks' deal after sources told Wojnarowski that the sides failed to come to an agreement on a new contract.
Portland is also finalizing a deal for LA Clippers assistant Roy Rogers to join Billups' staff, sources said. Rogers has shown an ability to help improve team defenses in recent stops and will focus on that end for the Blazers.
Rogers will work with a first-time head coach in Billups, who also spent the 2020-21 season as a Clippers assistant.