Sharks open to trading star defenseman Erik Karlsson this offseason

San Jose Sharks and Erik Karlsson's representatives agree that a trade is possible.
Karlsson wants to win and may not want to stay with the Sharks during their rebuilding.
Any trade of Karlsson would be complex due to his high salary and no-movement clause.
Karlsson's trade value may never be higher after a successful season.
Sharks GM Mike Grier wants a good return for Karlsson and won't trade him just for cap space.