Celtic have reportedly already made an approach for former Tottenham Hotspur boss Jose Mourinho.
The 58-year-old was sacked by Spurs on Monday following a run of one win in his final six matches, ending a 17-month spell in North London.
Mourinho has hinted that he is keen on a swift return to management, with Celtic among those rumoured to be interested in the Portuguese.
According to Duncan Castles on the Transfer Window Podcast, the Scottish giants wasted little time in contacting Mourinho's representatives following his sacking.
Celtic, who missed out on a 10th successive league title this season, are on the lookout for a new manager after parting company with Neil Lennon in February.
Mourinho is also believed to be a target for La Liga side Valencia and Serie A outfit Roma.
