The Pittsburgh Steelers will have to search elsewhere for cornerback help.

Free agents Patrick Robinson and Sterling Moore, who each visited the Steelers earlier this week, have signed one-year contracts with other teams.

Robinson signed with the San Diego Chargers on Thursday while Moore signed with the Tampa Bay Buccaneers.

The Steelers have signed only one free agent (running back DeAngelo Williams) and have only four cornerbacks on their roster with NFL experience.

They lost Brice McCain, who tied for the team lead with three interceptions in 2014, when he signed a two-year contract with the Miami Dolphins last week.

Cornerback and outside linebackers remain the Steelers’ biggest needs and they had a large contingent at Missouri's pro day to get another look at one of the top pass-rushers in the draft.

Shane Ray, who projects as an outside linebacker in a 3-4 defense, won SEC Defensive Player of the Year honors after notching 14.5 sacks last season. Ray is a sure-fire first-round pick but there are questions about whether the 6-foot-2, 245-pounder is more than just a speed rusher.

ESPN’s Mel Kiper Jr. ranks Ray as the ninth-best player in the draft but ESPN’s Todd McShay has dropped Ray to No. 15 in his draft rankings.

Ray ran on Thursday after skipping most of the drills at the NFL scouting combine last month because of a foot injury.

Steelers coach Mike Tomlin, general manager Kevin Colbert, defensive coordinator Keith Butler, outside linebackers coach Joey Porter and pro scouting coordinator Brandon Hunt all attended Missouri pro day.