According to The Scottish Sun, Celtic scouts have been watching Rijeka defender Marko Leskovic, and could pursue a £1.5m deal in January.
The Bhoys saw loan star Jason Denayer head back to Manchester City over the summer before joining Galatasaray, and manager Ronny Deila suffered another blow when fellow defender Virgil van Dijk left Celtic Park for Southampton on deadline day.
Celtic looked to replace their outstanding centre back duo with Dedryck Boyata and Jozo Simunovic, but the former has had an inconsistent start to the season, whilst the latter has suffered some niggling injury problems early in to his Bhoys career.
With a number of poor defensive showings this season, Celtic are widely expected to add another centre back in January - and it seems that another Croatian could be targeted.
Just months after landing Simunovic from Dinamo Zagreb, Celtic are pursuing Rijeka star Marko Leskovic, according to The Scottish Sun.
They report that Bhoys scouts have once again gone over to Croatia to seek defensive reinforcements, and Leskovic is their prime target having been impressed with his recent performance against Hajduk Split.
The 24-year-old has three caps for Croatia, and is allegedly valued at around £1.5m - and the report states that the player is friends with Simunovic, who could help convince Leskovic to make the move to Scotland over other interested clubs.
Whether it's Leskovic or another defender, Celtic certainly need to make at least one addition to their backline when the January transfer window opens, and Leskovic could be their man due to his relationship with Simunovic, with their familiarity potentially creating a more solid Celtic defence.