Erat will miss his second game since being driven into the boards by Florida Panthers defenseman Erik Gudbranson in the first period of a 4-3 Capitals win Saturday. Ward was hurt when he blocked a Sami Salo slap shot with his left leg in a 4-2 win Sunday against the Tampa Bay Lightning.
Ward and Erat made the trip to Montreal, but coach Adam Oates said each needs more time before returning to the lineup.
"[Ward] is still hurt pretty good from that shot," Oates said. "He came on the trip in case he got better, but he just wasn't feeling good this morning. Marty's just loosening up, but he's not quite ready yet."
Oates said there was no timeline for the return of either player.