After missing Pittsburgh's past two practices, Sheary is listed as week to week with a lower-body injury sustained in a 5-2 win against the San Jose Sharks on Tuesday. He has 19 points (12 goals, seven assists) in 52 games this season.
Forward Bryan Rust will move from fourth-line right wing, where forward Ryan Reaves could play Friday, to Sheary's spot on the first line.
The Penguins will try to match their season-long four-game winning streak. Pittsburgh is 8-2-0 in its past 10 games.
The Capitals, who lead the second-place New Jersey Devils by five points in the Metropolitan Division, will attempt to win their third straight game following a three-game losing streak (0-1-2). They have scored nine goals in their past two games after scoring six in their previous three.
Washington, 8-2-2 in its past 12 games, lost 3-2 to Pittsburgh on Oct. 11 and defeated the Penguins 4-1 on Nov. 10.