Otsemobor, a former youth international was brought to Millmoor by Mick Harford in the summer, fighting off competition from several other clubs including Crewe, but he failed to make an impact making just seven starts. He was the subject of interest from Walsall in October, who wanted to take him on loan but he was not allowed to leave as numbers were short.
The ex-Liverpool man's move to Crewe should free up space and wages for Alan Knill to bring in some reinforcements but looks set to miss out on former Doncaster centre half Steve Foster who looks almost certain to join Scunthorpe.