Former Socceroo star Harry Kewell will not return to action for Melbourne Heart in its must win clash with Adelaide United on Sunday afternoon.

Winless all season, coach John Aloisi has been at the centre of media speculation about his future, but on Saturday morning he told reporters he had not been given any ultimatums by the club's board.

Harry Kewell will not play against Adelaide United on Sunday. Credit:Wayne Taylor

But, he said Kewell, who was widely expected to return this weekend, would not.

"He hasn't come through a training session as well as we would have liked. There is no point risking him unless he is fit. There are still 20 games to go," he said.