The forward rejoined the Knights in December after a brief stint with St Albans Saints.

Mikulic scored one goal in three appearances for the Knights this season.

The 20-year-old came through the club's youth ranks and broke into the NPL Victoria in 2016.

"Ever since I was a boy playing soccer I’ve always wanted to become a professional player and with some hard work and perseverance, I have the opportunity to make my dream come true," Mikulic told the Knights website.

“For me personally this is my first stepping stone to become the professional footballer I would like to be.

"Hopefully it opens more windows of opportunity for the future.

"Thanks to the Melbourne Knights community for all their support and well wishes, I hope I can make us all proud.

"I couldn’t be happier signing with a club like FK Austria Wien. The club’s professionalism and standards are above expectations."

He will be joined by fellow Australian Jimmy Jeggo who has transferred from Sturm Graz late last week.