The Florida Panthers might have lost one of their top young defensemen to an offseason training injury according to a report from Harvey Fialkov of the Sun Sentinel.

According to the report, 20-year-old defenseman Erik Gudbranson suffered a potentially serious shoulder injury during an "informal" workout this past week that could keep him out of the lineup as long as four months.

If it proves to be a worst-case scenario and he misses significant time, it would be a big blow to the Panthers' blue line. Gudbranson, the third overall pick in the 2010 draft, had his first taste of the NHL last season and appeared in 72 games for the Panthers, scoring two goals with six assists.

The Panthers' defense already took a hit this offseason when Jason Garrison left in free agency to join the Vancouver Canucks. The team signed Filip Kuba to help replace him.

Florida has one of the league's deeper collections of young prospects, and Gudbranson is a big part of its future as a physical, shutdown defenseman.

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