Tony Popovic leaves Perth Glory to take on European role

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Perth Glory owner Tony Sage says coach Tony Popovic is leaving the club with his blessing, denying there is any animosity over the parting of ways.

Popovic, who still had one more year remaining on his Glory contract, has left the A-League club in order to take up a deal in Europe.

The veteran coach is yet to reveal where he is going next, but rumours are rife he will take over as coach of Xanthi, who have just been relegated from the Greek Super League and have reportedly been bought by Sydney Olympic president Bill Papas.

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Sage said there was an out-clause in Popovic's contract allowing him to take up a deal in Europe.

Popovic left the Western Sydney Wanderers in the lurch in 2017 when he took up a deal with Turkish side Karabukspor on the eve of the 2017-18 A-League season.

But it seems as though the parting of ways has been much smoother this time around, with Sage even nominating Popovic as the next Socceroos coach.

"There's no animosity, everything is fine between him and me," Sage told AAP. "It's a fantastic opportunity for him.

"He's done fantastic for the club, he loves the club. But clauses in contracts ... just like players, I never stop anyone from going. Never have, never will.

"It's an opportunity for him to expand.

"He brought us our first big silverware of the A-League era, so I wish him very well for the future."

Popovic led Glory to the Premiers Plate last season before they fell to Sydney FC on penalties in the Grand Final.

This season, Glory beat Wellington Phoenix in an elimination final before being bundled out by eventual premiers Sydney 2-0 in the semifinals.

Sage said the uncertainty surrounding next season played a major role in Popovic's decision to leave.

"I mean no one knows what's going to happen next year. The border restrictions are going to create havoc," Sage said.

"He lived in a bubble for seven weeks, so I don't think he wants to live in a bubble next year for five months if Perth has to play in a bubble somewhere.

"So if you're the coach and you've got another opportunity and you've got an exit clause, would you not take it? Or would you stay in the uncertainty of the A-league. That was one of the biggest things in his mind."

Sage said the future of skipper Diego Castro would be up to the new coach.

Castro's future is in doubt after he opted against joining his teammates in their NSW hub to finish the season.

Reports emerged Castro refused to play after being told he would need to take a pay cut.

The next A-League season was set to kick-off in December, but Sage expects the FFA to delay that by at least a month or two.