"The Buffalo Bills decided Saturday their investment in injured linebacker Shawne Merriman is worth some more time and money.

The Bills signed the former Pro Bowler to a two-year contract extension.

The Bills claimed Merriman off waivers Nov. 2 but didn't get any return on the move because Merriman's injured Achilles tendon has not allowed him to hit the field. Merriman was placed on the injured reserve list Nov. 27.

Now Merriman has plenty more time to get healthy enough to hit the field in a Bills uniform. The Bills paid him $1.7 million for this season, which turned out to be a down payment on a new deal. His extension is worth $10.5 million over two seasons, with $2.5 million guaranteed, according to a league source.

Bills General Manager Buddy Nix ran San Diego's scouting operation when the Chargers drafted Merriman in the first round in 2005. Merriman had 39.5 sacks his first three NFL seasons. But he missed 15 games in the 2008 season due to knee surgery. He played 14 games in 2009 but was plagued by nagging injuries and had only four sacks. He played in three games for the Chargers early this season, but his Achilles wasn't right, and San Diego waived him.

The Bills desperately need more playmakers on their defense, which ranks 24th overall, 32nd against the run and tied for 28th in quarterback sacks. Their need for an impact pass-rusher has been heightened by the lack of production from 2009 first-round draft choice Aaron Maybin.

Merriman is only 26 years old. The Bills think committing to him is a risk worth taking, given what he has done on the field when he has been fully healthy.

Merriman continues to rehabilitate his Achilles tendon, and he's not scheduled to have any surgeries on it. The Bills expect he will be ready for spring practices."