Misfiring forward David Fernandez has returned to Livingston from Celtic on loan.
David Fernandez has rarely featured in a Celtic jersey
The two Scottish Premier League clubs have agreed a deal until the end of the season, although the situation can be reviewed during the next transfer window in January.
News of the Fernandez deal will increase speculation that Celtic could beat Sunday's transfer deadline to make a major signing.
Celtic manager Martin O'Neill had said on Friday that he would not allow Fernandez to leave unless he had first signed a replacement.
But, after his side had thumped Livingston 5-1 at Celtic Park, he said: "He needs match fitness and he feels, at this minute, that he might not get the opportunity here.
"So he hasn't given up on it, but he wants to get match fitness and a bit of extra confidence needs restoring.
"Knowing our luck, we will be releasing somebody and then start struggling with injuries, which is always the case.
"But he needs the benefit of matches and we will then see what the situation is like in January."
O'Neill also said he had not given up on making a signing before the closure of the transfer window.
"I am keeping going to the last minute and, in the last four or five days, I have been all over the place," he said.
O'Neill had been in negotiations with new Rangers signing Emerson but withdrew his interest because of the Brazilian midfielder's wage demands.
Livingston chairman Dominic Keane told BBC Sport of his delight that Fernandez is returning to the City Stadium, the Spaniard having helped the club to a good first season in the SPL before leaving for Celtic Park.
Dundee had also been interested, but Fernandez preferred to return to familiar surroundings in an attempt to recapture his form.
Meanwhile, Keane, who described his side's performance in Glasgow as "diabolical", was on Saturday evening busy trying to complete the signing of a defender presently playing abroad.