Oshie and defenseman John Carlson, who is day to day with a lower-body injury, did not play Monday when Washington lost 3-2 in a shootout at the Carolina Hurricanes. Each was injured in the first period of a 3-0 win at the Nashville Predators on Saturday.
The Capitals were already without forwards Tom Wilson (torn anterior cruciate ligament injury in right knee), Nicklas Backstrom (resurfacing surgery on left hip), Carl Hagelin (surgery on left hip, eye injury) and Connor Brown (ACL surgery). Although Wilson and Backstrom started skating lightly last week, Wilson is not expected to play before December and Backstrom is out indefinitely. Hagelin and Brown are also out indefinitely.
"It feels a little like last year," forward Lars Eller said. "We were always missing five, six guys in the lineup. Now we're facing a similar scenario, so it's not foreign to us. But we're going to miss them. They're important players for us. But for now, we've got other guys who can step up and do the job. We'll get a little bit more from everyone, and I still think we'll be able to grind out games."
Oshie has five points (two goals, three assists) in nine games this season. He played two shifts Saturday before coming up lame while chasing the puck in the offensive zone during a Washington power play.
The 35-year-old had core surgery this summer after having 25 points (11 goals, 14 assists) in 44 regular-season games last season. He missed 38 regular-season games because of multiple injuries (fractured foot, back, upper body) and illnesses (COVID-19 protocol, non-COVID illness), but had seven points (six goals, one assist) in six Stanley Cup Playoff games.
"He's been through it with some injuries," coach Peter Laviolette said. "It's going to weigh on you mentally sometimes too. Then the physical part of rehabilitating and getting back in the lineup. So, there's a lot that goes with it. He's a pretty positive person by nature, and he will work hard to get back."
Carlson appeared to be injured when he fell awkwardly in the left corner in the defensive zone while trying to knock the puck away from Nashville forward Zach Sanford. The 32-year-old has six points (two goals, four assists) in nine games this season and, with 599 points (134 goals, 465 assists) in 896 regular-season games, is one away from becoming the fifth Capitals player, and first defenseman, to reach 600 points.
NHL.com independent correspondent Kurt Dusterburg contributed to this report