Nilsson has found his game lately with four goals and two assists in his last eight games for the IceHogs. The 25-year-old, who stands at 5-foot-11 and 181 pounds, has six goals and 14 points in 31 AHL games in his first North American season.
Nilsson signed a one-year contract in May. He had eight goals and 18 points for Mora IK in Sweden last season.
Blackhawks head coach Jeremy Colliton is familiar with Nilsson after coaching him for two seasons with Mora IK.
Johnson, 24, played just 6:55 minutes across 11 shifts in Chicago’s 2-1 victory Friday at Colorado. The 2013 fifth-round draft pick had one shot the night before in the Blackhawks’ 5-2 win at Dallas. He has one assist in 15 NHL games this season, and seven points (four goals, three assists) in 10 AHL games for Rockford.
The Blackhawks host the Panthers on Sunday at the United Center, while the IceHogs return from their Christmas break Wednesday against the Wolves at Allstate Arena in Rosemont.