Zeljko Buvac's absence from Liverpool is due to a falling-out with manager Jurgen Klopp, according to a report.
Sky Sports News claims that Bosnian coach has stepped away from his post as the Reds' assistant manager due to a bust-up with his superior.
Liverpool have offered no official explanation for Buvac's absence, confirming only that he has made the decision to temporarily depart for "personal reasons".
Previous reports from the coach's native Bosnia claimed that he has left Anfield to replace outgoing Arsenal manager Arsene Wenger at the Emirates Stadium.
The latest reports suggest that he travelled to Mainz in Germany when the Liverpool squad headed to Rome for the second leg of their Champions League clash with Roma.