Spagnuolo was let go by the Rams Jan. 2 after they finished with a 2-14 record, including seven straight losses to end the season.
In three seasons at the helm in St. Louis, he compiled a 10-38 record.
Spagnuolo formerly was defensive coordinator for the New York Giants, helping guide them to a Super Bowl victory over the New England Patriots following the 2007 season.
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