The Dutch coach got the green and gold playing promising football but they couldn't make the most of it - failing to score from open play at the World Cup.
Van Marwijk's decision to leave veteran striker Tim Cahill on the bench against Denmark drew plenty of criticism, with some believing the conservative decision cost the Socceroos dearly.
Mark Milligan begs to differ, and shut down those being critical of the departing coach.
"They don't know," Milligan said.
"They're not here everyday. They've no idea.
"You wouldn't find many more experienced coaches than Bert, so if people know enough to be questioning him, they know more than me.
"Bert did an absolutely wonderful job. It would have been nice if he'd had a little more time, given what he's done with us in a short period of time."
Milligan has now been included in four World Cup squads for Australia with the 32-year-old playing every game in Russia.
While clearly still able to cut it at international level, Milligan admitted he's got some thinking to do about his future as a Socceroo.
An emotional post-match exchange with his family forcing the defender to take stock of things.
"My emotions were quite different to theirs," he said.
"I asked my eldest daughter what was the matter and she just said, 'You've been away too long'.
"So, they just put things into perspective."