The Oakland Raiders are the first NFL franchise to dip their toes into the restricted free agent market this season, as Ian Rapoport of NFL.com is reporting that the team has signed Green Bay Packers safety Sean Richardson to an RFA offer sheet.

"#Raiders have signed Packers RFA safety Sean Richardson to an offer sheet, source said. Green Bay can match, but there is no compensation," Rapoport tweeted.

As Rapoport stated and Darin Gantt of Pro Football Talk points out, the Packers are owed no compensation should they choose not to match the offer sheet.

"The Packers will have a chance to match, but would get no compensation if they don't, since Richardson was an undrafted rookie and the Packers tendered him at the lowest level," Gantt writes.

According to Adam Caplan of ESPN, the Packers have until April 13 to decide whether or not to match.

The 25-year-old Richardson is set to enter his fourth NFL season out of Vanderbilt. He's got good size at 6-foot-2, 216-pounds but as Gantt notes, recently recovered from neck surgery.

Despite the procedure, Richardson returned to the lineup for the Packers and finished the 2014 season with 25 tackles in 16 games, giving him 42 total tackles for his career and no interceptions or forced fumbles.

"Richardson runs extremely smooth and fast, although he doesn't get to full speed often," reads NFL.com's pre-draft assessment of Richardson. "When he does, he could compete with the fastest in the league at his position. He has strong ball skills, and when he puts these two traits together, Richardson is an impressive safety. He has the natural ability to start in the NFL if he can shore up different technical weaknesses he has."

The Raiders still have the ageless Charles Woodson and handed former Philadelphia Eagle Nate Allen, who they signed to a four-year, $23 million contract with $11.8 million guaranteed, after releasing Tyvon Branch at the outset of the latest league year.

It's doubtful that Richardson would come to Oakland with an expectation to perform as anything other than a key special teamer and battle with Jonathan Dowling, Brandian Ross, Larry Asante and Ras-I Dowling for the No. 3 role.