FILE - In this Nov. 24, 2013, file photo, New York Jets safety Ed Reed walks off the field after an NFL football game against the Baltimore Ravens in Baltimore. The Buffalo Bills announced Wednesday, Jan. 13, 2016, that Reed agreed in principle to be an assistant defensive backs coach on Rex Ryan’s staff. (AP Photo/Patrick Semansky, File)
FILE – In this Nov. 24, 2013, file photo, New York Jets safety Ed Reed walks off the field after an NFL football game against the Baltimore Ravens in Baltimore. The Buffalo Bills announced Wednesday, Jan. 13, 2016, that Reed agreed in principle to be an assistant defensive backs coach on Rex Ryan’s staff. (AP Photo/Patrick Semansky, File)

Five-time All-Pro safety Ed Reed is reuniting with Rex Ryan. This time on the Buffalo Bills’ sideline.

The Bills announced on January 13 that Reed agreed in principle to be an assistant defensive backs coach on Ryan’s staff.

Reed spent his first seven seasons in Baltimore playing for Ryan, who was the Ravens defensive coordinator. And Reed ended his career in 2013 playing for the Ryan-coached New York Jets.

“I can attest to the incredibly high level of professionalism he is going to bring with him to Buffalo,” Ryan said in a statement released by the team. “I think he’s going to be a phenomenal coach and I truly believe our players are going to love learning from him.”

Reed was the NFL’s 2004 defensive player of the year, a nine-time Pro Bowl selection and helped the Ravens win the 2013 Super Bowl. His 64 career interceptions rank seventh on the NFL list, and Reed holds the league record with 1,590 yards in interception returns.

As a player, Reed was regarded for his extensive game preparation and ability to analyze game film. He was also noted for tutoring his teammates.

The move is the latest in a series of shuffles made to the Bills’ defensive staff.

On Sunday, Ryan hired his twin brother Rob to serve as assistant head coach responsible for defense. On Tuesday, the Bills fired third-year defensive backs coach Donnie Henderson.

Buffalo is coming off an 8-8 finish, and extended the NFL’s longest active playoff drought to 16 consecutive seasons. Their high-priced defense underachieved last year in its first season after Ryan took over as coach.

Buffalo finished 19th in yards allowed, a year after ranking fourth.

The Bills have two established starters at cornerback in Stephon Gilmore and Ronald Darby, who had a solid rookie season.

The secondary has question marks at safety after starter Aaron Williams missed most of the season with a neck injury. Ryan expects Williams to return next season.