The San Francisco 49ers will be leaning more heavily on the veteran presence of Randy Moss as they ramp up preparations for the postseason.

Wide receiver Mario Manningham has been lost for the season with a gruesome left knee injury – he tore the ACL and PCL in his left knee. He’s the second receiver to go out recently as Kyle Williams was already placed on IR and now Moss will need to raise his level of play, according to Matt Barrows of the Sacramento Bee.

Moss has 10 receptions for 140 yards and one touchdown in the last four games. He’d played sparingly with only five catch in the previous five games. With Michael Crabtree and tight end Vernon Davis as primary targets in the passing game, Moss will have to deliver in order to keep opposing defenses honest or otherwise the 49ers will need Ted Ginn Jr. or first-round pick A.J. Jenkins to suddenly deliver. Ginn and Jenkins have done very little this season.

The 26-year Manningham had made 42 receptions for 449 yards and one touchdown. He’s obviously experienced in the postseason and that will be another loss for the Niners, who are suddenly dealing wit injuries at a difficult point in the season.

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Brad Biggs covers the Bears for the Chicago Tribune