Melbourne Heart is hoping to learn by Friday lunchtime whether it will be without marquee signing Orlando Engelaar for the remainder of the season following the Dutchman's nightmare debut for the club in Lismore at the weekend.

Engelaar sustained a broken leg in a challenge early in the pre-season friendly defeat against Brisbane Roar. With his surgery set for Thursday night, Heart has been told it will know by Friday lunchtime how long the former Netherlands international will be out for. The best case scenario is three months – which is unlikely, and the worst case seven months, which would effectively rule Englelaar out for the entire campaign.

Melbourne Heart FC marquee signing Orlando Engelaar at AAMI Park on August 20. Credit:Getty Images

His injury leaves Heart in a difficult situation regarding both personnel and team structure.

John Aloisi, the Heart coach, planned to build his midfield around the tall Dutchman, using him as the pivot behind a front four with Massimo Murdocca as the box to box player alongside. As football manager John Didulica said on Thursday, "Engelaar is the type of player we have been looking for for a long time."