Pittsburgh Steelers' free-agency update

The Pittsburgh Steelers' players returned to work Monday when the first phase of the offseason program started. The next two weeks will be limited to lifting and conditioning, and there is still more than a month before the Steelers begin full-team practice sessions.

Players will be added through the draft and signing of undrafted free agents. Here are the unrestricted free agents the Steelers signed. I will have a post later today looking at the restricted free agents the team retained.

OLB Arthur Moats, three-year, $7.5 million contract, $1.483 million salary-cap hit in 2015: Moats is the starting left outside linebacker for now. That could change based on the Steelers' draft but he will likely get the first crack at replacing Jason Worilds. Moats quietly gave the Steelers solid play last season as he recorded four sacks and forced two fumbles and made 10 starts at right outside linebacker. Moats is only 27 years old and re-signing him was a no-brainer, especially given the terms to bring him back.

RB DeAngelo Williams, two-year, $4 million contract, $1.435 million cap hit in 2015: Williams figures to be the Steelers’ feature back to start the season with Le’Veon Bell suspended for the first three games. Bell’s suspension likely will get knocked down to two games but the Steelers needed a proven veteran like Williams, the Carolina Panthers' all-time leading rusher. They aren't finished adding to the position either. The Steelers have taken at least one running back in seven of eight drafts since Mike Tomlin became their head coach. Look for them to take another one this year on the third day of the draft.

OLB James Harrison, two-year, $2.75 million contract, $1.25 million cap hit in 2015: So much for the thinking that the Steelers would wait until after offseason practices to re-sign Harrison. The Tennessee Titans compelled the Steelers to act because of their interest in Harrison and the five-time Pro Bowler is the last man standing in one aspect. Harrison is the only remaining defensive player on the teams that played in three Super Bowls from 2005-10. Harrison's leadership will be almost as important as his pass-rushing skills in a locker room that won’t have defensive end Brett Keisel, strong safety Troy Polamalu and cornerback Ike Taylor in it next season.

TE Matt Spaeth, two-year, $2.2 million contract, $1.063 million cap hit in 2015: Spaeth doesn’t give the Steelers much in the passing game but he is a valuable blocker and gives offensive coordinator Todd Haley a trusted player to pair with starter Heath Miller in two-tight-end sets. The re-signing of Spaeth does not reduce the Steelers’ need to draft a young tight end, and they could address that position early.

S Will Allen, one-year, $1.05 million contract, $665,000 cap hit in 2015: The Steelers re-signed Allen shortly after announcing the retirement of Polamalu. The 11th-year veteran gives them insurance should Shamarko Thomas falter at strong safety -- as well as a veteran presence in the defensive backfield. Allen, who has given the Steelers solid play as a No. 3 safety and spot starter the past two seasons, is not a lock to make the team in 2015 if the Steelers take a safety early in the draft.

LS Greg Warren, one-year, $1.05 million contract, $665,000 cap hit in 2015: Warren keeps fending off challenges for his job and he will have to do so again this year. The Steelers claimed long-snapper Brandon Hartson of waivers late last week and he has his work cut out for him. Warren has been so steady as a long-snapper and has such a good rapport with the other specialists that the Steelers keep bringing back the 10th-year veteran.

WR Darrius Heyward-Bey, one-year, $825,000 contract, $665,000 cap hit in 2015: Heyward-Bey, the seventh overall pick of the 2009 NFL draft, caught just three passes last season. But his speed made Heyward-Bey a key contributor on special teams as did his willingness to help in that phase of the game. The Steelers are top-heavy at wide receiver and there could be an opening for Heyward-Bey as a No. 4 wideout. But the draft is ridiculously loaded at wide receiver for the second consecutive year and the Steelers are going to take one at some point. The only question is where and that will impact Heyward-Bey’s role next season.

DE Clifton Geathers, one-year, $825,000 contract, $665,000 cap hit in 2015: Geathers did not dress for any games after the Steelers signed the journeyman early last December. But the Steelers saw enough from the 6-foot-8, 325-pounder to bring him back at a position where they are set with starters Cameron Heyward and Stephon Tuitt but need depth. It will be interesting to see if the Steelers take a defensive lineman in the draft and where.