Moussa Dembele finally got his move from Celtic to Lyon for almost £20m after an initial rejected bid sparked open dissent from the Frenchman.
Celtic boss Brendan Rodgers refused to sanction the deal on Thursday without an adequate replacement lined up.
But the club performed a U-turn after Rodgers felt Dembele's antics on social media and the training field threatened the culture of the squad ahead of Sunday's visit of Rangers.
It was a fitting end to a difficult transfer window for Celtic which saw Rodgers miss out on two of his top three targets and end up a striker down plus holding an unhappy player in Dedryck Boyata, who missed out on a move to Fulham and saw no late move to the continent emerge.
Celtic did complete two deals on deadline day though as former West Brom and Kilmarnock midfielder Youssouf Mulumbu signed a two-year contract and Leicester defender Filip Benkovic completed a season-long loan.
