The Whites came close to landing Zuparic during the January transfer window. Despite having since been relegated from the Premier League the West London side remain interested.
However, they face competition from the Blades – who can offer top flight English football to Zuparic next season. This is after their promotion from the Championship.
Zuparic is about to enter the final year of his current contract. This is why the 27-year-old is available for the relative bargain price of just £1.5m.
Who is Zuparic?
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The centre-back is a former Under-21 and Under-20 international with Croatia. Prior to that Zuparic represented Bosnia and Herzegovina at Under-19 level due to his dual nationality.
The Croatian spent the early part of his career in his native country, coming through the ranks at Cibalia. Then in the summer of 2013 Zuparic left for Italy, joining Pescara.
The defender spent three-and-a-half years with the Italian team, helping them gain promotion to Serie A in 2015/16. The following January he returned to Croatia, initially joining Rijeka on an 18-month loan.
Zurapic helped the club to their first ever Croatian First League title that first season, along with victory in the Croatian Cup. In the summer of 2018 his move became permanent.
Rijeka won the cup again this season, beating Dinamo Zagreb in a shock 3-1 result in the final. Zuparic was named man of the match.
Due to their impressive recent form domestically, the former Under-21 international has also been given an opportunity on the European stage. Zuparic has played in the Europa League group stages and Champions League qualifying.
Despite being considered a central defender, the versatile Croat also plays as a defensive midfielder.