Popovic shocked the Australian football community on Sunday with confirmation he was leaving the club he has guided since their inception five seasons ago to join Turkish outfit Karabukspor.
"The timing certainly is not great, you don't plan these things, but it's come up very recently and it's an opportunity to get my foot into the door in Europe in a big competition and that's where I'd like to take my next challenge," Popovic said, just a week out from the start of the new A-League season.
When asked if he would be taking any of his coaching staff with him, the 44-year-old refused to answer.
"That's not something that I want to talk about now, the main thing is that I've decided I'm going," he said.
The former Socceroo did concede that some of the talks with Karabukspor involved who else was currently contracted in their coaching department.
CEO John Tsatsimas said the club had yet to appoint an interim coach until it was made clear who Popovic would be taking with him.
"The people we have in our football department are well versed in what's happened in pre-season, it would certainly be folly of us to rush in and make an appointment particularly with a match only five or six days away".
Western Sydney host Perth in round one of the new A-League season next Sunday.
The club hopes to make a call on their short term options in a day or so, Tsatsimas said.
"I've had better Sunday mornings," Tsatsimas lamented before insisting the club would remain strong.
"We'll take our time to make the right appointment."
Popovic's current contract was due to run until the end of the 2017-18 season after re-signing for three years in mid-2015.
The Sydney United junior was the Wanderers' first coach when they entered the A-League in 2012, and guided them to consecutive grand final appearances in their first two seasons.
Popovic also steered his side to a famous win in the Asian Champions League final in 2014, earning him the AFC coach of the year award.
He was subsequently linked to a Premier League move at Crystal Palace which didn't eventuate but now has the chance to prove his wares in Europe.
"This one was in a league which I think is in a very strong level - it's in Europe - and I want an opportunity to coach in Europe. It's an opening for me to do that and to have success in Turkey," Popovic said.
