Newcastle Jets have confirmed the departure of coach Scott Miller, citing "differences related to football matters".
The 34-year-old had only been in charge of the Jets for a season, guiding the 2008 Australian champions to an eighth-place finish in the 10-team league, following eight wins from 27 matches.
"We acknowledge that the timing of this decision is far from ideal given the close proximity of next Hyundai A-League season," Jets chief executive Lawrie McKinna said in a statement.
"But once the decision was made to move in a different direction regarding the head coach role we deemed it to be in everyone's best interests to act quickly."
The Jets open their A-League season against defending champions Adelaide United on October 9.