The 20-year-old key defender will undergo the first of two operations to repair his shoulders on Thursday afternoon.
Hartley has only played two VFL games in the last 12 months. He managed to play half a game against the Northern Blues in a practice match earlier this year but was forced from the field after injuring his shoulder.
As a result, he underwent an arthroscope on both shoulders in March and returned against Coburg in the week before the mid-season bye.
Unfortunately, Hartley reinjured his shoulder against the Tigers and will now miss the rest of the season.
“He’s having surgery on his right shoulder today,” Director of Football Geoff Walsh told collingwoodfc.com.au.
“He needs both shoulders repaired. That would mean that probably six weeks down the track from now that he’ll have the other one repaired which will end his season.”
View Collingwood's full injury list here.
Hartley revealed that he was in the wars against Coburg, wearing a big blow to the face as well as his shoulder.
“I hurt it pretty badly against Coburg,” he said.
“I had one real big episode on the right one which was the worst.
“I’ll get my right shoulder done first then the left one in a couple of weeks.
“I got smacked in the face. I didn’t break my nose but it was badly bruised. It looked a bit weird but it isn’t too bad”.
Hartley was originally recruited to the club via the NSW Scholarship program in 2008.
He began to train full time at the Westpac Centre last year and made an impression in his four NAB Cup matches before injury intervened.
Send your best wishes to Michael on Twitter at @MichaelHarts47.
"Under the knife again soon #waitinggame #surgerysucks #havenotateanythingforAgesssssss" - Instagram @michael_harts47
