Did Vlasic get a concussion/TBI when he got hit by the puck on Gostisbehere's shot in Dec 2016? I always wondered about that. I can't remember if that was the start of his recent decline or if his decline preceded that.
IAE, if this is his second (or third) TBI, his prognosis for full recovery is not nearly as good as if he only had one. Either way, a concussion could mess up almost anything related to his play (skating, judgment - especially at speed, timing, passing, etc.) but if the decline preceded any TBI, it might be a contributing factor but clearly not the sole cause of his decline.