Gartside recalled to talkSPORT: "The full story never actually came out. What happened was Didi signed for us on a free transfer from Liverpool, came in, signed the papers, and then, for whatever reason, decided it wasn't for him and that he wanted to reconsider.
"We said to you, 'I'm sorry about that, but you've signed' but what he never realised was that we never actually countersigned the papers and just put them in the drawer.
"The next thing we know, he came along and told us he'd got this opportunity to go to Manchester City - so we actually sold him without actually signing him, did you know that?
"We got £400,000 from Manchester City for a player we never actually signed. And that's the truth."
Hamann appeared bewildered by the chairman's claims and jested: "I didn't know that, we might need to get in touch with City."
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