Dumais (lower body) will not be in the lineup against Buffalo on Monday, Jeff Svoboda of the Blue Jackets' official site reports.
Dumais has yet to make his NHL debut but could be in line to do so this season. Even without his lower-body injury, the 20-year-old winger seemed unlikely to make the Jackets' Opening Night roster. Instead, Dumais figures to make the jump to the professional ranks and join AHL Cleveland after four seasons with QMJHL Halifax.