Chargers sign free-agent guard Ohrnberger

The San Diego Chargers signed former Arizona Cardinals guard

Rich Ohrnberger to a one-year contract Thursday.

Heading into his fifth season, he has played in 18 career games

and started four.

He was drafted by New England in the fourth round in 2009 out of

Penn State. He played in five games his first two seasons with the

Patriots, seeing limited time at right guard and on special teams.

Ohrnberger spent the 2011 season on injured reserve due to a head

injury and was released in February 2012. He signed with Arizona

and played in 13 games last year, making two starts at both right

guard and center. He suffered a knee injury on Dec. 9 against

Seattle and was placed on injured reserve.

Ohrnberger becomes the sixth unrestricted free agent to join the

Chargers, and the third offensive lineman.