Rams sign former Green Bay Packers cornerback Sam Shields

The Rams made another move that affects their secondary by signing veteran cornerback Sam Shields, the team announced Thursday.

Shields, 30, was an integral part of the Green Bay Packers’ defense from 2010 to 2015, but he was sidelined for nearly all of the 2016 season after suffering the fourth known concussion of his pro career. He did not play last season.

The 5-foot-11, 184-pound Shields has 18 career interceptions.

He joins a Rams defense that is undergoing rapid change.

In the last few weeks, the Rams have agreed to deals that will enable them to acquire star cornerback Marcus Peters from the Kansas City Chiefs, send linebacker Robert Quinn to the Miami Dolphins and send linebacker Alec Ogletree to the New York Giants.

The trades will not become official until Wednesday, the first day of the NFL’s new league year.

The deals have enabled the Rams to amass 10 draft picks in the April 26-28 draft, five in the sixth round. They also are expected to have more than $40 million in salary-cap space when free agency begins next week.

Coach Sean McVay, general manager Les Snead and defensive coordinator Wade Phillips are looking for players that fit Phillips’ 3-4 scheme.

Immediately after the season, with veteran cornerback Trumaine Johnson bound for free agency and fellow starter Kayvon Webster coming back from a season-ending Achilles injury, the Rams were thought to be targeting cornerbacks with the 23rd pick in the draft.

But the focus could change with the arrival of the 25-year-old Peters, who has 19 interceptions in three NFL seasons and is under contract for $1.7 million in 2018.

Peters, Webster, Shields, Troy Hill and Kevin Peterson could be among the cornerbacks on the roster once Peters passes a physical next week.

Nickell Robey-Coleman, who played well as a slot cornerback last season, is a pending free agent. The former USC standout has expressed a desire to remain with the Rams.

Johnson will test the market after playing under the franchise tag the last two seasons. The Rams have not ruled out approaching Johnson with a long-term deal once they gauge his price on the open market.

The signing of Shields comes two days after the Rams put the franchise tag on safety Lamarcus Joyner, who will earn $11.2 million next season if he and the Rams do not work out a long-term deal by July 16.

gary.klein@latimes.com

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