Kevin Muscat has been forced to make a public apology for his horror tackle in the Melbourne derby.
The 37-year-old Melbourne Victory defender was given a red card for a knee-high tackle on Adrian Zahra.
Melbourne Heart fear the winger will be out for the rest of the season - and Muscat now faces a long ban.
"The tackle was terrible," said Heart coach John van't Schip. "It doesn't fit on the football field and hopefully it's not going to end the young career of a great player."
Muscat has previous when it comes to reckless challenges. He paid £250,000 in compensation to Matty Holmes in 2004 after a challenge which ended the Charlton midfielder's career.
The former Australia defender, who also had spells at Rangers and Crystal Palace, was suitable contrite the day after: "Having had a sleepless night I felt it was important to front up and accept everything that is going to be coming my way in relation to bans and suspensions and being criticised and my character and my performance and all that comes with it.
"I have to accept full responsibility for it but my only concern is the welfare of Adrian.
"It was an incident that I deeply regret. It was a mistimed tackle, dreadfully mistimed.
"At no point did I have any intent to injure the player. My only concern is the welfare of Adrian.
"I wish him a speedy recovery and in the next couple of days I'll take the opportunity to try to contact him and pass on my sentiments if he'll accept them.''
Muscat, who had just returned from suspension, hinted he could now retire.
"I badly mistimed a tackle. Maybe it is telling me the game has passed me by."