Sydney FC were first given, then denied their chance at a second-successive A-League Championship by the boot of Terry Antonis.

Melbourne Victory's 3-2 win in extra-time is the final match for Graham Arnold as Sky Blues boss, with the 54-year-old now set to take the reigns as Socceroos coach following the 2018 World Cup.

"It's sad to be leaving but I'm proud of what we've achieved here," Arnold said.

"I didn't really think about not having to go to work tomorrow. I've had a fantastic time here with a great group of people, the wonderful fans, a great rivalry with Kevin Muscat.

"It's a bit sad but I can walk away very proud of the job that I've done here."

After the bravado - even arrogance - that he's been famed for throughout his Sydney tenure, Arnold offered a humble, composed tribute to his opposition.

"I give full credit to Melbourne tonight," he said.

"It wasn't our best performance, we were fortunate enough with two own goals, which shows we weren't quite on song tonight. Full credit to Melbourne.

"(Finals) are one off games, it's a final series. We finished 20 ponts ahead of them in the league. We finished with eight men, (Michael) Zullo was spent, Bobo was spent.

"I still say we are (the greatest A-League side of all time).

"When you finish 31 points clear of your opposition over two years, sometimes you don't get your just rewards.

"But I'm very proud of the two years we've had, breaking so many records along the way."