With Burnley boss Sean Dyche reportedly being a big fan of the Bosnian defender, there is certainly plenty of interest down south that Celtic will have to consider.
Currently valued at up to £8 million, Brendan Rodgers may be prepared to once again rake in some cash for the Scottish Champions, whose budget is nothing near the money that English clubs have available.
The 23-year-old has Champions League experience this season but has had his ups and downs in the heart of the defence alongside Dedryck Boyata. A standout performance came in the 3-0 away win against Anderlecht but he also had a nightmare performance when Celtic saw their first defeat of the season away at Hearts last month.
Domestically, Simunovic has only started nine games this season and has struggled with a hamstring problem, ruling him out of some important games for Celtic, meaning that Rodgers could have to seriously consider any big money offers that come in.
A move does seem possible with the emergence of young Kristoffer Ajer, who has been chosen over Simunovic in recent weeks, including for the Old Firm game, showing that he may have slipped down the defensive pecking order.
If any move does go through it would leave the Hoops light in defence with Erik Sviatchenko also seemingly heading for the Parkhead exit door. New signing Marvin Compper is also unable to play against Zenit St. Petersburg in the last 32 of the Europa League, so this could potentially be a stumbling block to any transfer deal.