Mike Green sat out of Monday's 3-2 loss to the Phoenix Coyotes with an "undisclosed injury," but now the nature of the injury has become known.

Via Washington Post's Katie Carrera, head coach Bruce Boudreau told the media that Green has "inner ear trauma." According to Boudreau, although Green hadn't been feeling well, he was still able to make the five-game road trip.

On February 6, Green left Washington's 3-0 victory over the Pittsburgh Penguins after taking a Brooks Orpik slap shot to the side of the head. Green would sit out of Tuesday's 2-0 loss to the San Jose Sharks, but returned Saturday in a 4-1 loss to the Los Angeles Kings. Green said last week that he felt "100 percent," so his absence from Monday's game is much more concerning.