Nose tackle Isaac Sopoaga has agreed to terms with the Philadelphia Eagles on a three-year contract worth close to $12 million with approximately $5 million guaranteed, a source said.
Sopoaga, who played his first nine NFL seasons with the 49ers, visited the Eagles on the first day of free agency. His previous contract with the 49ers was a five-year, $20 million deal. Sopoaga becomes the second 49ers free agent to leave on the first day of free agency. Earlier, tight end Delanie Walker agreed to terms on a reported four-year, $17.5 million contract with the Tennessee Titans.
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Sopoaga played about one-third of the team's offensive snaps as a starter. When the 49ers went with extra defensive backs, Sopoaga was the first player to come off the field.
The 49ers are also in danger of losing backup nose tackle Ricky Jean Francois, who is also visiting the Eagles. On Monday, the 49ers signed third-string nose tackle Ian Williams to a two-year extension through the 2015 season.
The 49ers have a visit scheduled with Kansas City Chiefs free-agent defensive tackle Glenn Dorsey on Wednesday.
[RELATED: Dorsey set to visit 49ers]