R's boss Neil Warnock accused Blackburn striker El-Hadji Diouf of verbally abusing Mackie as he lay on the ground injured during Saturday's game.
QPR lost the FA Cup third round tie at Ewood Park 1-0.
Scotland international Mackie suffered the double fracture in a collision with Rovers defender Gael Givet, who was also carried off.
The Football Association is reviewing the incident involving Diouf.
Source: BBC Sport
Source: BBC Sport