The England international was left out of Saturday's 7-0 victory over Norwich City following a string of errors since Pellegrini took charge at the Etihad Stadium in the summer.
However, rather than voice his disappointment at being replaced by Costel Pantilimon, Pellegrini has insisted that Hart believes that "a rest will be useful for him".
"Joe has reacted very well. For him this is a good thing after playing so many matches over the past two or three years. He has been working no problem, supporting Costel. Nobody wants to be out but he thinks a rest will be useful for him too," the Chilean manager told reporters.
Pantilimon is expected to continue between the posts during City's Champions League clash with CSKA Moscow tomorrow evening.