Baccus will be hoping his move to the Scottish club will enhance his chances of making Graham Arnold's Socceroos squad, with the World Cup in Qatar in November.

The midfielder made over 100 A-League appearances for the Red & Black over eight years, making him the second-highest capped player of all time behind Mark Bridge.

He won the club's highest accolade - the Wanderers Medal - twice.

Though he leaves with a heavy heart, the chance to play in Europe was too good to turn down.

"It's a little bit sad leaving my hometown, family that I can say I've made at this club and all the members and fans that have been great to me," said Baccus.

"Same as the coaches, the coaching staff and everyone, it's been great. I've loved every minute.

"Now moving onto my next chapter, it's going to be good and it's going to be special."

Western Sydney Wanderers CEO Scott Hudson thanked Baccus for his contribution.

"Having known Keanu since the first day he arrived at the Wanderers, it has been an honour to see him grow from a young boy to a man at the club that means so much to him," said Hudson.

"The door will always been open for Keanu to one day return to the club and we will always be supporting him from afar."

Australian Associated Press