The St. Louis Blues got one of their top players back Sunday but lost another later in the day.
Allen has been out with a lower-body injury. Steen has an upper-body injury and will be re-evaluated in four weeks, the team announced.
Steen was injured Saturday night, leaving with 12:52 left in the first period against Arizona after he was hit by Coyotes defenseman Kevin Connauton. Steen has 47 points (17 goals and 30 assists), which ranks second on the team.
The Blues had been able to withstand Allen's injury, going 12-3-2 during his absence thanks to Brian Elliott's stellar play in front of the net.
Allen, 25, who has been out since the Blues' game against the Anaheim Ducks on Jan. 8, has an 18-10-3 record this season with a 2.17 goals-against average and .924 save percentage. He has five shutouts this season.
Elliott, 30, recently had a streak of three straight victories in which he allowed only one goal (Feb. 14-18). According to ESPN Stats & Information, it's the second time this season that a Blues goaltender had won three consecutive games while allowing no more than one goal in each game. Allen accomplished the feat in a stretch of games Nov. 4-10.
Elliott is 17-7-6 this season with a 2.06 GAA, a .931 save percentage and one shutout.
St. Louis, at 35-17-9, is third in the Central Division standings with 79 points.