Central Coast Mariners striker Roy O'Donovan has received an eight game suspension for his headbutt on Wellington Phoenix defender Manny Muscat.

"The Player pleaded guilty to the offence of 'Assault on a Player (e.g. violent conduct when not challenging for the ball)'," the FFA said in a statement.

"The Disciplinary Committee determined that the Player must serve a suspension of eight (8) matches.

"The Player has the right to appeal the determination of the Disciplinary Committee. If the Player intends to do so, he must advise FFA within 7 days of receiving the written determination."

Mariners CEO, Shaun Mielekamp said after the hearing that the club will most likely appeal the length of the ban.

“We are extremely disappointed at this decision, the disparity in sanctions issued for this match, which highlights the flaws in the system," Mielekamp said.

"The media circus around the incident has had a high impact on the result and we will look at our avenues for appeal."