Castillo was the longtime offensive line coach for the Eagles before an ill-fated stint as their defensive coordinator.
According to the Ravens' offensive and defensive coordinators, both Castillo and Spagnuolo have fit in well as new additions to the staff.
"Juan is a veteran with a lot of experience. He’s been around the block a bit, and he’s coached a lot of good players," offensive coordinator Jim Caldwell said. "From a schematic standpoint, obviously, he has helped us tremendously, not only in our running game, but also with our pass game as well. He’s been an integral part of the discussions that went on during the offseason. He’s doing a great job. Obviously, the guys listen to him. They gravitate towards him. He’s a diligent, hard-working guy, and he knows his craft."
A former St. Louis Rams head coach, Spagnuolo was the defensive coordinator when the New York Giants won Super Bowl XLII and was the defensive coordinator for the New Orleans Saints last season before being fired after finishing last in total defense. He has coached in the NFL for 14 years.
He was the linebackers coach for the Eagles when Harbaugh was in Philadelphia.
During the 2007 NFL season, the Giants ranked in the top 10 in eight statistical categories as they led the NFL with 53 sacks.
Now he has a versatile role with the Ravens' coaching staff.
“Steve is a guy that kind of whatever we ask him to do – whether it’s draw cards, whether it’s to do a special project, no matter what it is, it’s kind of nice to have him here to bounce stuff off of and also it just takes a load off of other guys having to do some of the things that he’s doing," defensive coordinator Dean Pees said. "He’s trying to learn our defense at the same time, and it really kind of helps him if we give him some responsibility, because then he has to dig into it. He’s doing a great job. I’m very pleased that he is here.”