Devastating news for Clarke MacArthur

Ottawa Senators forward Clarke MacArthur made a surprising return to the NHL lin April despite having been ruled out for the year after a training camp concussion.

Well this year's training camp is not any better. The forward failed his medical on Thursday. 

MacArthur has sustained four known concussions since joining the Senators in 2013. He had not dressed in a game since Oct. 14, 2015 when he returned in April.