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Wide receiver Mario Manningham agreed to a $1.8 million pay cut in his base salary for the 2013 season, an NFL source confirmed Thursday.
The new contract, first noticed by Jason Hurley of NinersNation.com, reduces Manningham's base pay from $3.6 million to $1.8 million. Of his salary, $1.25 million is guaranteed for injury only.
The new contract eliminates a possible $250,000 roster bonus, as well as a $100,000 workout bonus and incentives, the source said.
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Manningham signed a two-year, $7.4 million contract with the 49ers last March. He was the team's second-leading receiver with 42 catches for 449 yards and one touchdown despite playing in 12 games.
He sustained tears to the anterior cruciate and medial collateral ligaments in his left knee on Dec. 23 against the Seattle Seahawks. He underwent surgery nearly a month later after the swelling subsided.
The 49ers do not expect Manningham to be ready for the opening of training camp, but he believes he will be available for the start of the regular season. Manningham is not likely to be a starter this season after the club's acquisition of Anquan Boldin in a trade with the Baltimore Ravens for a sixth-round draft pick. Michael Crabtree led the 49ers in receiving last season with 85 catches for 1,105 yards and nine touchdowns.
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The 49ers had $9.29 million in salary cap room before Glenn Dorsey's contract, which has not yet been tabulated by the league, the source said.