-- Sam Shields is back in the headlines with the intentions of resuming his NFL career after being sidelined for 18 months.

The former Green Bay Packers cornerback isn't letting concussions or potentially severe head trauma get in the way of a comeback. The 30-year-old Shields will visit teams this week, a source told ESPN's Adam Schefter. He has visits lined up with the Cleveland Browns and Los Angeles Rams.

Shields hasn't played since suffering what was his fourth reported concussion in a six-year span in week 1 of the 2016 season against the Jacksonville Jaguars. The concussion he suffered in that game was also his second in the previous nine months after his previous concussion caused him to miss the final three games of the 2015 regular season and the Packers' wild-card game against the Washington Redskins.

Since being placed on injured reserve in October of 2016 and subsequently released in February from the team that originally signed him as an undrafted free agent in 2010, Shields has been relatively out of sight and out of mind. Aside from having his home searched one day after he was released by the Packers and leading to two counts of marijuana possession.

It's unclear whether or not Shields will have to serve a two-game suspension with whoever signs him, but that's just the minor risk a team would take if they were to pursue him.

Despite Shields claiming that he's back to full health and there isn't much to worry about in terms of his concussion history, it's undoubtedly still a factor that teams will most certainly consider. Not only is it a gamble financially, but it's a gamble for Shields' personal well being.

The Packers -- as it stands -- aren't one of the teams that are interested in Shields, and realistically, they shouldn't be. His untimely end to what could've been a stellar career in Green Bay is missing its final chapter that Shields never had the opportunity to write on his own terms. Instead, the toll of the game helped him see his way out.

He can still play, and as he told Michael Cohen of the Milwaukee Journal Sentinel: he can still run, too.

"I think I'm back to my normal self," Shields said. "I can just take one day at a time and try to keep conditioning to get myself ready for whatever. March or April, whatever team picks me up so I can be ready to go." 

Shields' six months spent at a UCLA rehab facility during the tail-end of the Packers' 2016 season to help minimize his ongoing headaches that came as a result of his repeated concussions. Evidently, his rehab left him feeling like he still has a competitive edge that he can bring to an NFL roster.

Whether that roster resides in Green Bay or not is the only barrier between nostalgia and reality.

The Packers drafted Kevin King with their 33rd overall selection in last year's draft and have received an uproar in production from Damarious Randall through the final 10 games of last season. The Packers will more than likely draft a cornerback in the early rounds of this year's draft to complete the starting trio, and then sign a veteran cornerback for depth while letting Davon House back on the market.

It would seem like there's no room for Shields, and while you can never have enough cornerbacks with instinctive cover ability like Shields once possessed, the Packers moved on from Shields the moment they released him in February of last year.

If any reunion were likely among the current crop of free agent cornerbacks, it would be Tramon Williams, who forced the lowest passer rating (58.4) amongst free agent cornerbacks when targeted last season, according to Pro Football Focus.

Only Patrick Peterson, Charles Woodson and Richard Sherman had more interceptions than Shields' 16 from 2011-2015.