Captain Jack Eichel will not suit up against the Flyers due to a lower-body injury which the forward has been dealing with since training camp.
Goaltender Linus Ullmark is expected to miss a month after suffering an injury against the New Jersey Devils on Thursday.
Skinner — who's in Year 2 of a deal that pays him $9 million per season, making him the team's second-highest-paid player — has not played a game since Feb. 20, missing the last three games as a healthy scratch. The 28-year-old forward has recorded just one assist in 14 games for the Sabres this season.
Ristolainen returns to the lineup after recovering from COVID-19. The 26-year-old defender spoke recently about his battle with the virus, telling Finnish newspaper Ilta-Sanomat that he dealt with symptoms including severe chest pains and significant drops in oxygen levels.