The Rangers midfielder’s father Zlato is currently the manager of Croatian side Dinamo Zagreb.
And after the Hoops reached the qualification play-off round on Wedesday night, they could meet Zagreb in Friday’s draw.
Brendan Rodgers’ side went through a nervy test against Kazakhstan outfit Astana before sealing a late win thanks to a Moussa Dembele penalty in the dying minutes.
The Parkhead side are aiming to reach the group stages for the first time since 2013 after failing under former boss Ronny Deila in the last two qualification bids.
Celtic’s other possible opponents in the draw include Dundalk, Hapoel Beer Sheva, FC Copenhagen or Ludogorets Razgrad.
Former QPR ace Kranjcar is set to make his league debut for the Light Blues this weekend against Hamilton Accies after appearing in Betfred Cup games against Motherwell, Annan, East Stirling and Stranraer.
But this should be one of his toughest competitive tests yet as a Rangers player.
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