Tampa Bay Lightning defenseman Mattias Ohlund began a long, grueling rehab this week after having knee surgery in February. Ohlund starts the process with his future in professional hockey still in doubt, according to the Tampa Bay Tribune.

Doctors at the Cleveland Clinic inserted a titanium plate on Ohlund's femur where the kneecap connects. The cartilage that usually protects the bones had eroded away in Ohlund's joint, causing the bones to rub together. It was so painful that he missed all of last season and has not been on skates since November.

Getting back on the ice will take some time, and doctors note that people who undergo this kind of procedure do not typically return to a high-intensity activity like professional ice hockey.

Lightning general manager Steve Yzerman said that the team was not planning to have Ohlund back to start the season.

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