The team said Wednesday that Grabovski has an undisclosed lower body injury. He left Tuesday night's shootout loss in the third period after a collision at center ice.
MacArthur, ruled out of Thursday night's game at Nashville, didn't play after the second period because of an undisclosed upper body injury.
The Maple Leafs did get some good news, however, on Wednesday. Toronto coach Ron Wilson said that Tim Connolly is expected to play Thursday against the Predators. He has been out with an upper body injury.