Celtic coach Ronny Delia confirmed the Scottish Premier League champions could not complete the signing of Ghana midfielder Mubarak Wakaso on Tuesday due to paperwork problem.
The Bhoys had wanted to finalize the one-year loan deal from Russian Premier League side Rubin Kazan before their Champions League playoff tie.
Wakaso underwent medical in Moscow and was expected to tie up the deal but that was not to be.
If the deal had gone through, the 24-year-old would have been eligible to face Slovenian side Maribor.
Delia told a press conference: "Itâ€™s going on. It doesnâ€™t seem like there will be anything today. Hard because of paperwork."
Wakaso played a bit-part role for Ghana at the 2014 World Cup.
RD on Mubarak Wakaso latest: "Itâ€™s going on. It doesnâ€™t seem like there will be anything today. Hard because of paperwork." #UCL (MH)
â€” Celtic Football Club (@celticfc) August 19, 2014