The 21-year-old joined The Citizens in a £3.5 million deal from Independiente in the summer, but has yet to taste even one minute of first-team action.
Now the Argentine youngster has hit out at Keegan saying the former England boss has not even spoken to him about why he has yet to figure.
"I haven't even spoken to him," raged Vuoso.
"I find it strange he doesn't play meÇª it was an expensive transfer, but maybe he doesn't think well of me, maybe he was expecting something else of me.
"I'm not the kind of player who says much whether I'm playing or not playing, so for the time being I will just leave it.
"If I never play though I will speak out and will see what to do.
"I have nothing against Keegan even if he decides I'm not right for the team, but I can't go on not playing for much longer."
Vuoso admitted he had settled well in England and would be keen to stay in Manchester.
The forward has bagged eight goals in nine reserve outings, but refused to rule out the possibility of moving on if Keegan continued to overlook him.
"I wouldn't rule it out (moving), if I did it would be to another club in Europe," he said.
"But I feel good here, living in Manchester is very special."