Donatell, 61, has worked as the defensive backs coach under Fangio since 2011, with four years apiece spent in San Francisco and Chicago.
Only new offensive line coach Mike Munchak has been a confirmed addition.
On top of officially removing the interim tag on Offensive Coordinator Kevin Stefanski's position, hiring former Broncos and Texans head coach Gary Kubiak to an advisory role, and bringing Kubiak's son, Klint to the quarterbacks coach position, news has broke that the Vikings have brought on Brian Pariani as the new tight ends coach for the upcoming season.
After working two years at Millsaps College, where the team led its league in scoring both seasons, Scangarello moved to Northern Arizona.
Scangarello earned high marks for his work with quarterback Nick Mullens, whom he suggested the team sign following injuries.
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Listed as an offensive quality control coach, Scangarello stayed in the spare bedroom of a Falcons assistant, but wanted to be around Shanahan, whose system he had been studying for years.
Under offensive coordinator Bill Musgrave, the Broncos built a bad habit of starting slowly. He already spends the early part of practices with that group, working alongside LaFleur and special offensive. Hafley left the 49ers to serve as co-defensive coordinator under new Ohio State coach Ryan Day.
While he will have the title of defensive coordinator in Denver, Fangio will be the defensive play-caller.
Pagano, who was named to succeed Vic Fangio as the Bears' defensive coordinator Friday, is coaching in the NFLPA Collegiate Bowl on Saturday in the Los Angeles area. Woods comes to the 49ers in a supporting role for defensive coordinator Robert Saleh.
"When he recently became available, we acted aggressively to add him to our staff because his philosophy, and the style of play he coaches, fits our scheme and personnel very well", Shanahan said.
"I have a ton of respect for him, and it's mutual between both of us".