Hiroki Sakai (Marseille)
Another exciting prospect could be Marseille right-back, Hiroki Sakai. Sakai has been a regular fixture for Marseille since joining from Hannover in 2016.
The Japanese is an attacking right-back whilst also strong defensively with top tackling traits. He can play at left-back and in central defence if required.
Sakai would offer vast experience to this Celtic side after serving stints in Japan, Germany and France. With that in mind, the powerful performer could be a straight upgrade on Lustig.