German coach Frank Pajelsdorf, who trained Al Nasr four years ago, could be the Croatian coach's successor.
The club board has appointed Cristophe Jordan, the reserve team coach, to take care of the senior team until they sign a new coach. Jordan will lead the team in the the etisalat Cup match against Al Ain on Friday.
"The Pajelsdorf signing could be completed soon. We have agreed on almost 90 per cent of his contract's conditions. We have temporarily appointed Austrian coach Cristophe Jordan as caretaker until the new coach arrives," said Al Nasr club manager Ahmad Al Ghaith.
Bonacic began with Al Nasr at the beginning of 2008 when Al Nasr were at the bottom of the league table. He contributed in lifting the team to the middle of the table and promised to compete for titles in the current season.
The Croatian, however, had problems with Al Nasr players. He sought to sell the best players to other clubs.
As a result, Al Nasr lost young and talented players like Darwish Ahmad, Khalid Sebil, Abdullah Moussa, Walid Murad, Ali Abbas, Salah Abbas, Adnan Hussain, Yousuf Moussa, Mohammad Ali Ghuloom and Abdul Rahman Khalfan.
Bonacic also created problems for new players like Adil Nasib, Yousuf Abdul Aziz, Salim Zayed and Mohammad Ennazy, who signed for Al Nasr at the start of the season.
He reportedly did not want these players in the senior team and switched them to the reserves.
Al Nasr supporters claim Bonacic was responsible for the signing of Iranian players Mohammad Nasrati and Redha Enayati, who have showed poor form.
Al Nasr are lying seventh in the professional league with 12 points from 10 matches.
They also lost in the President's Cup pre-quarterfinals to Al Khaleej.