Boo Nieves is not participating in Tuesday’s practice and there is concern that it is concussion-related, per the New York Post’s Larry Brooks.

Nieves injured his head following a hit from New Jersey’s Eric Gryba in Monday night’s preseason game, and he did not return for the remainder of the game.

It must first be stated that the primary concern here is medical. Concussions are a serious matter, and this would not be the first of Nieves’ career. In terms of hockey, though, this is poor timing for both the Rangers and Nieves. The fourth-line center spot is wide open, and it’s possibly now-or-never for the 2012 second-round pick. A prolonged absence would effectively take him out of the competition.