The Oakland Raiders make their first big move of 2017

Jack Del Rio made his first coaching staff change since becoming the Oakland Raiders' coach in 2015, promoting quarterbacks coach Todd Downing to offensive coordinator, the team announced Saturday.

Downing replaces Bill Musgrave, who served as OC for the past two seasons but was not offered a new contract. Musgrave joined new Denver Broncos coach Vance Joseph's staff as quarterbacks coach on Friday.

The Raiders had a top-10 offense last season and secured the team's first playoff berth in 14 years, and Downing's work with Derek Carr turned the third-year QB into one of the NFL's best. Carr completed 63.8 percent of his passes for 3,937 yards, 28 touchdowns and six interceptions before breaking his leg in Week 16.

Downing's assistant, Jake Peetz, has been promoted to quarterbacks coach. Del Rio is yet to name a new defensive backs coach after Marcus Robertson was not offered a new contract. The Raiders allowed a league-leading 61 passing plays for 20-plus yards last season.