The defender is currently on loan from Borussia Dortmund.
However, Toljan couldn’t create the impact that he was expected to do and has been sidelined for over a month, owing to injury.
The 24-year-old has appeared for 10 matches so far and received a red card in the Europa League clash against Valencia.
Now, Carlo Ancelotti’s side are interested in the right-back Toljan. Yet, his injury woes could be a concern for the Italian side.
Napoli were eliminated from the Europa League in the quarter-finals against Arsenal. They are second in the Serie A table, with Juventus already being crowned the Champions with games to spare.
Moreover, the German is tied up with Dortmund until 2022.
It is also expected that the Hoops are having no plans of extending the former Stuttgart man’s loan spell.
Neil Lennon is currently enjoying his spell at Park Head as the interim manager.
The former Hibernian manager has led his side to a string of wins since taking the charge midway through the season.
His notable victories include the Old Firm win, followed by the qualification into Scottish Cup finals.
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The Celts are likely to win their eighth straight Premiership title this season and possibly could achieve a domestic treble as well.
They will be facing Hearts in the Cup final next month.