Mailloux, 22, has been held without a point while posting a minus-12 through his first nine games with the Blues.
St. Louis acquired the Belle River, Ont., native from the Montreal Canadiens in a trade for forward Zack Bolduc on July 1. Bolduc has six points (four goals, two assists) in 15 games with the Habs on the season.
The Blues, meanwhile, have struggled out of the gates, sitting second-last in the West with 13 points in 16 games. Mailloux was recently sidelined as a healthy scratch.
Skinner, 24, will be making his NHL debut if and when he first hits the ice.
The Wyandotte, Mich., native was selected in the fourth round (112th overall) of the 2019 draft by the New York Rangers.
He has one goal and one assist in 11 games with the AHL’s Springfield Thunderbirds on the season.
