49ers WR Manningham to start season on PUP list

San Francisco 49ers wide receiver Mario Manningham will begin the season on the reserve/physically unable to perform list.

Manningham, who is rehabbing a knee injury that he suffered in a loss in Seattle late last year, will not be eligible to play in the team's first six games of the regular season.

"It's going very well," 49ers coach Jim Harbaugh said of Manningham. "Been great feedback on Mario. He's really feeling now that he can put his leg in the ground and generate some power."

Manningham caught 42 passes for 449 yards and one touchdown in his first season with the 49ers. He spent the first four years of his career with the New York Giants.

Harbaugh also commented on the rehab status of fellow wide receiver Michael Crabtree, who sustained an Achilles injury in offseason workouts.

"He's hit every single goal as far as his timeline," Harbaugh said. "That's been real exciting and encouraging."

However, Crabtree is also likely to be placed on the team's reserve PUP list. The Texas Tech product caught 85 passes for 1,105 yards and nine touchdowns in 16 games last season.