Forward Adam Cracknell also was recalled from Peoria of the American Hockey League.
Allen has been recalled under emergency conditions due to goaltender Jaroslav Halak’s lower body injury, which he suffered during the first period in the Blues' 4-1 win against the Minnesota Wild on Monday night.
Allen has appeared in 12 games with the Blues this season, posting an 8-3-0 record, 2.45 goals-against average and a .906 save percentage.
Oshie has dressed in 30 games this season, tying for fifth on the club with 20 points (seven goals).
Cracknell has dressed in eight games for the Blues this season, posting two assists.