Mantha notched two assists and two hits in Tuesday's 5-4 overtime loss to the Predators.
Mantha was traded from the Capitals to the Golden Knights on Tuesday, Darren Dreger of TSN reports.
Mantha scored a power-play goal in Sunday's 5-2 loss to the Coyotes.
Mantha registered a power-play goal during Friday's 5-2 win over the Flyers.
Mantha logged a pair of assists in Monday's 6-3 win over the Senators.
Mantha (lower body) is on the ice for warmups prior to Monday's tilt against Ottawa, Tom Gulitti of NHL.com reports.
Mantha (lower body) will be a game-time decision Monday versus Ottawa, per Bailey Johnson of The Washington Post.
Mantha tallied a goal and an assist in Saturday's 4-3 win over Montreal.
Mantha logged a pair of assists in Tuesday's 6-3 loss to the Avalanche.
Mantha produced a goal and an assist in Saturday's 5-4 overtime loss to the Stars.