Liam Lawrence has joined Portsmouth on an emergency loan from Stoke in a deal which will become permanent in January.
The Championship club thought they had snapped up the Republic of Ireland winger on transfer deadline day only to find they had not completed the paperwork in time.
But the Football League have now ratified the switch, and Stoke chief executive Tony Scholes said: "This solution means we will eventually arrive at the same point as the original transfer when the permanent move goes through in the January window."
He added: "It is particularly pleasing that this has been resolved in a favourable way for Liam because he had been left in limbo after making his mind up to join Portsmouth.
"He has been a magnificent servant for this club and was hugely popular with the supporters, so everyone at the club wishes him well in the future."
Lawrence said: "I'm delighted it's all done and now I just want to get out there and play for Portsmouth.
"Steve Cotterill has been a massive influence on me coming here. He was so positive about the club and about my move.
"I'm coming to a huge club and it's now up to us to turn things around. We're hoping it will be onwards and upwards for the season."