For the second time in three years, strong safety Brian Walker has departed the Miami Dolphins, and this time he probably won't come back.

The Dolphins' starting strong safety for the past two seasons, Walker has agreed to contract terms with the Detroit Lions and will receive a five-year, $10 million deal that includes a signing bonus of $2 million. The agreement was hammered out in Indianapolis at the scouting combine.

Walker, 29, will be a welcome addition to a Detroit secondary that suffered a rash of injuries in 2001. The Lions lost three different safeties to major injuries and shuffled the lineup the entire year. The former Washington State standout should provide stability and leadership to a unit that figures to undergo a revamping this spring.

A six-year veteran, Walker had 99 tackles for the Dolphins in 2001 despite sitting out three games with a thumb injury. In 2000, he had seven interceptions, the most by a Miami safety since Jake Scott had eight in 1974.

Walker began his career with the Washington Redskins in 1996 as an undrafted free agent. He was waived by the Redskins in '97 and signed with Miami as a free agent. In 1999, the Dolphins released him in September and he signed with Seattle. He then re-joined Miami in 2000.

Over the past two seasons, Walker has been one of the most dependable strong safeties in the NFL, with 164 tackles.

The loss of Walker could leave Miami without either of its starting safeties from 2001. The team released free safety Brock Marion last week but will attempt to re-sign him at a lower price than he was scheduled to make. The Dolphins have also initiated contract extension discussions with young safety Arturo Freeman, who saw substantial playing time in 2001.

Len Pasquarelli is a senior writer at ESPN.com.