The 17-year old reigning Jets Player of the Year was admitted to hospital twice after the 2-1 win over Central Coast Mariners last Friday with what was thought to be a case of appendicitis but turned out to be a virus he may have picked up when away in Egypt with the Australian U20 team for the World Cup earlier this month.
"At about midnight I started to get really bad stomach cramps," Kantarovski said.
"They got worse and worse and I ended up going to hospital. Initially they thought it was my appendix.
"I had some blood tests and it ended up being a virus. I went home early Saturday morning but after a couple of hours the cramps returned and were stronger. I couldn't walk.
"I went back to hospital, they admitted me and dosed me up with morphine and antibiotics.
"They think I might have picked up something from the water when I was in Egypt [for the Under-20 World Cup] earlier in the month."
The Year 12 student said he expects t be right for the vital clash with the Roar at Suncorp Stadium, which kicks off at 7:30pm local time (8:30 AEDT) tomorrow.
"I still have a bit of pain with my stomach, but I should be close to 100 per cent by Friday," he added.