Skysports.com understands former Liverpool full-back Gregory Vignal is training with Sheffield United in the hope of securing a permanent move.
The French left-back is currently without a club after Birmingham boss Alex McLeish released him at the end of last season.
Vignal, 28, was plagued with injuries last term and was restricted to just nine first-team appearances for the Blues during his one-year stay.
His Premier League experience has attracted interest from Blades boss Kevin Blackwell, and he will look at the Frenchman closely in training over the coming days.
Vignal made his name at Liverpool after arriving at Anfield from hometown club Montpellier for £500,000 back in 2000.
He found first-team appearances hard to come by under former Reds boss Gerard Houllier though, and was loaned out to a number of European clubs - including Rangers - before moving to Portsmouth at the start of the 2005 campaign.
Once again he struggled to break into the first-team and he joined RC Lens on a free transfer the following season.
Further loan spells at Kaiserslautern and Southampton followed before McLeish signed him on a one-year deal at the start of last season.
Vignal could be the second full-back to sign at Bramall Lane in a matter of days after Rob Kozluk re-joined the club last week.