(Reuters) - Eight weeks after being cut by the Buffalo Bills, former Pro Bowl defensive end Shawne Merriman rejoined the National Football League team on Monday to help alleviate a spate of injuries.

The Bills are already without defensive end Mark Anderson, who had surgery last week to repair an injured left knee, and defensive tackle Spencer Johnson, who has missed two games because of an ankle injury.

"You can never have too many guys that we believe can rush the passer," Buffalo head coach Chan Gailey told reporters. "We would rather not go into a game with just three defensive ends.

"We do not know how long Spencer is going to be, so we are going to sign Shawne back and hopefully he will give us some pass rush off of the edge."

Merriman, a 28-year-old former first round draft pick of the San Diego Chargers who was nicknamed "Lights Out" because of his hard hits, was released by the Bills on August 20 after an injury-plagued stint with the team.

Buffalo had originally acquired Merriman off waivers in 2010 in hopes that the player who led the NFL with 39.5 sacks from 2005-07 could help bolster their pass rush.

But an Achilles injury suffered in his first practice with the Bills prevented Merriman from playing that season. He had one sack in five games last year before being sidelined again to have surgery on his Achilles and to heal a shoulder injury.

Fellow defensive end Chris Kelsay was delighted to see Merriman back.

"It is always nice when you can bring a guy back that is acquainted and comfortable with the scheme and the system that we are in," Kelsay said.

"A guy that is a veteran who knows how to go about his business, he knows what is expected and he is going to come right in and pick up right where he left off."

The Bills are 3-3 this season in a tightly contested AFC East.