The St. Louis Blues and Buffalo Sabres will each be dealing with new lineups Thursday when they face each other at Scottrade Center. The Blues, already without forward Vladimir Tarasenko (thumb), will be missing forward Alexander Steen and defenseman Barret Jackman. Each has been ruled out for the game and are listed as day-to-day, according to coach Ken Hitchcock. "Steen is upper-body, Jackman's lower-body," Hitchcock said. "We'll see whether they're going to play on the weekend or not right now." Forward Dmitrij Jaskin will take Steen's spot on the top line with David Backes and T.J. Oshie, with Derek Roy shifting on and off that top line, according to Hitchcock. Defenseman Jordan Leopold, who has been nursing a high-ankle sprain, will replace Jackman. "It's been a long year," said Leopold, who missed 26 games earlier this season with a hand injury and another 18 since sustaining the ankle injury Feb. 8. "I'm excited to go out and play a hockey game instead of practicing with nobody. "It's not a very easy injury to deal with. It's unfortunate, but it is what it is. You go out there and deal with it as you go." The Blues (51-17-7) lead the Central Division and are one point behind the Boston Bruins in the race for the Presidents' Trophy. The Blues lead the Anaheim Ducks by one point for the Western Conference's top spot. The Sabres (21-45-9) could be without right wing Drew Stafford.