The 24-year-old forward spent the majoirty of the 2019-20 season in the Primeira Liga, joining Maritimo on loan from former club Matsumoto Yamaga, but failed to set the heather on fire, scoring only three goals in 23 appearances.
Meada blamed Covid for interrupting his spell in the Portuguese top flight, having previously been quoted as stating: “I’ve never hidden my ambition to play in Europe. When I tried before in Portugal, Covid ruined it for me.”
The speedy striker has enjoyed prolific form back in his homeland, finishing top scorer in last season’s J-League after netting 23 goals in 36 appearances for Postecoglou’s former side Yokohama F. Marinos.
Despite his limited impact at Maritimo, the Celtic boss is confident the Japan international will shine in Glasgow.
Speaking to Celtic TV, Postecoglou said: "Daizen is a determined character in terms of wanting to be the best that he can be.
“He had already had a stint in Europe in Portugal, but I could see it was unfinished business for him.
“He really wanted to come back and prove himself in Japan to hopefully get another opportunity.
“I was actually keen to try to bring him in during the summer window, but it’s very hard to get Japanese players to come across mid-season.
“Yokohama were doing well, and it was one I felt we could wait until January to bring him in, because I knew his attributes and I felt he would do well for us and in this league.”