The win brings Sydney FC's tally to 11 goals without reply in three games and sent Graham Arnold's side into the final of the FFA Cup.

Goals from Sebastian Ryall, Milos Dimitrijevic and the returning Bernie Ibini settled the result in front of 5,581 fans at Viking Park, but the Sky Blues were pushed all the way by their ACT opposition.

Olympic troubled the Sky Blues in the early stages of the match with their high defensive line, while striker Philippe Bernabo-Madrid had the first shot on goal with an athletic bicycle kick.

At the other end Bobo came close to opening the scoring midway through the first-half when he sprung the offside trap but Olympic’s goalkeeper Angelo Konstantinou made a strong save to deny his shot.

Seb Ryall opened the scoring from a short corner which found Rhyan Grant on the edge of the box who flighted in the perfect ball for Ryall's head.

Milos Dimitrijević doubled the lead in the second half with a thunderbolt freekick which left Olympic's otherwise excellent keeper Angelo Kostantinou at a standstill.

And in the dying moments of the game, Ibini came off the bench to replace Filip Holosko and thundered down the wing to get on the end of a cross from Matt Simon and buried it into the bottom corner.

The goal came in Ibini's first competitve game in 18 months after breaking his ankle soon after joining Club Brugge, who have now loaned him back to Sydney for this season.

Sydney now wait to face either Melbourne Victory or Melbourne City, who meet next Tuesday night. 

“It’s the first FFA Cup Final in the history of the club and it’s a wonderful feat for the players and for the club," said coach Graham Arnold after the game.

“That’s six wins and we are yet to concede a goal this season and we are scoring goals freely.  We missed our chances tonight and could have put Canberra away in the first half when we had the chances but overall it’s a pleasing result.

“I make no secret that I couldn’t be happier for Bernie Ibini.  He’s been out for a long time and has come back to Australia to get fit and healthy again.

“He’s only 30 to 40 percent of where he’ll end up but the kid has worked extremely hard and the medical staff have done a fantastic job on Bernie.  To see him finish it off there and score a goal makes it a special night for him.”