The 31-year-old underwent scans on Monday after sustaining the injury fielding for the Melbourne Renegades in the Big Bash League.
Doctors have confirmed Maddinson has ruptured his anterior cruciate ligament.
Maddinson’s rehabilitation plan will be confirmed over the coming days in consultation with Cricket Victoria medical staff.
“It’s very unfortunate news for Nic, he has been one of the leading batters in the country across the Sheffield Shield over recent years,” Cricket Victoria’s General Manager of Cricket, Graham Manou said.
“Nic has also been an outstanding leader within our young squad and I have no doubt he will continue to play that role through his rehabilitation process.
“We’re right behind Nic, we’ll provide our full support in any way we can.”
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