Port Vale manager Micky Adams remains interested in signing Colchester United striker Jamie Guy, even though he requires a knee operation.
Guy, 22, tore his cartilage in training on Thursday, just before he was due to sign for Vale on loan.
Adams told BBC Radio Stoke: "It was all agreed that he would sign on Friday, but he's gone back to Colchester now for a knee operation.
"We'll monitor the situation because he's someone I would like to sign."
Guy, who was set to make his Vale debut in the 1-1 draw against Rochdale on Saturday, is expected to be out of action for around three weeks.
Player-assistant manager Geoff Horsfield started the game, and Adams was pleased with his contribution.
"Jamie's injury messed up our preparations but Geoff, the old warhorse, came in and he gave me a good hour in difficult conditions. It was very hot out there," added the Vale boss.
Commentary of Vale's Carling Cup first round tie against Sheffield United at Bramall Lane on Tuesday, 11 August can be found on BBC Radio Stoke 94.6 FM with Matt Sandoz and Mick Cullerton from 1945 BST.
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