The 24-year-old sustained a knee injury in a challenge with Hoops centre-back Carl Starfelt and after receiving treatment from the physio, was taken off and replaced by Christian Doidge. He later left Easter Road on crutches with a brace on his left leg.
Manager Shaun Maloney is awaiting the outcome of a scan but admitted in the aftermath of the game that the early signs for the Scotland internationalist weren't good.
"It doesn't look too promising for Kevin. We'll probably find out later. It's his left knee," the Hibs boss explained.
"It wasn't the worst tackle ever, but when you try and stop a counter-attack like that, it's not great. It doesn't look too great at the moment."
Hibs already have six players out injured while another three were missing against Celtic due to a combination of illness and Ewan Henderson's ineligibility to face his parent club.
Speaking last week the Hibs boss cast doubt on any of his long-term absentees returning to action in the immediate future.
Harry Clarke hasn't kicked a ball since signing on loan from Arsenal in the January transfer window while fellow new signing Demi Mitchell is facing time on the sidelines after picking up an injury in the Scottish Cup victory over Arbroath. The 25-year-old has already allayed fears of season-ending injury but with Paul Hanlon, Kyle Magennis, Paul McGinn, and Joe Newell also unavailable, Maloney will be crossing his fingers that Nisbet's injury isn't too serious.