The 36-year old is a free agent having left Qatar club Al-Rayyan at the end of last season but Wanderers boss Sam Allardyce has offered the Real Madrid legend a twelve month deal having recently seen the player at close quarters during a successful trial.
Hierro spent 14-years at Madrid winning numerous medals including the Champions League alongside his good friend and current Bolton star Ivan Campo and Allardyce is hopeful that the loose ends can be tied up to bring the veteran to the club later this week.
"I’ve had talks with Hierro and his representatives over the weekend and he is keen to come to Bolton, I am confident that a deal can be done during the early part of this week." Allardyce told the official site
The Bolton boss feels that Hierro's experience and ability will be vital to the team and is happy with the Spaniards overall fitness and ability having been out of the top class game for over a year.
"He has a massive pedigree and I believe, despite him not playing top football in the last year, that he will be a great asset to Bolton Wanderers. His experience and ability will add much needed strength to our defensive line."
Big Sam is also still hoping to bring both Tal Ben Haim and Julio Cesar to the club after both completed successful trials during the pre-season build up. A need to add to the defence has been essential following the news that Florent Laville will be out until the winter and the fact that Emerson Thome, Simon Charlton and Steve Howey have all departed the club this summer.