The midfielder will be sidelined for more than two months after twisting his knee during the final day of the season against Celtic.
Hearts midfielder Olly Lee will miss Saturday’s William Hill Scottish Cup final with a knee injury.
The former Luton player faces more than two months out after twisting his knee early in Sunday’s league defeat by Hearts’ Hampden opponents, Celtic.
Manager Craig Levein told the club’s official website: “It’s hugely disappointing news for us, and especially for Olly.
“He twisted his knee on the pitch with nobody around him on Sunday and at the time it didn’t look too good, now we know that he’ll be out for around 10 weeks.
“Missing out on a cup final is hard to take so Olly now has to focus on his rehab and target making a comeback for the beginning of the next league campaign.
“We’ll continue to monitor the progress of Peter Haring and Arnaud Djoum this week, and I expect Harry Cochrane to return from illness, so we will have options in midfield for Saturday’s game.”
Haring (groin) and Djoum (Achilles) have missed recent games along with striker Uche Ikpeazu, who is working to overcome a hamstring issue.
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