The Queenslander suffered the injury while fielding last night.
Lynn clutched the joint in pain after attempting a catch to dismiss Jos Buttler in the outfield. He was attended to by Knight Riders' physio Andrew Leipus and was later seen with an ice-pack strapped to his shoulder.
After the match, Lynn tweeted, "Dear Cricket Gods, did I do something wrong?", indicating that he could be out of action for some time.
"He has undergone an MRI on his left shoulder. We will get to know the status of his injury in a day or two," read a statement from the media manager.
During the Australian summer, Lynn was a standout player in the BBL and also made his ODI debut for Australia.