By now, there have been enough incidents to justify raising that flag.
Latest was today, in her match against Patty Schnyder. Schnyder heard someone shouting just when Sharapova was about to serve. She raised her hand to signal a time out. Sharapova served anyways.
That was the first and the only ace of the match for Sharapova, since Schnyder did not even move.
There have been myriad of other instances, when she has taken questionable bathroom breaks just when her opponent gets hot, to break the momentum.
And of course, the now famous banana incident. Yuri, her father has been blatantly floundering the no-coaching rule, until the umpires came down heavy with fines and warnings, lately.
He was caught on TV raising a banana to ask her daughter to eat one. Same day her coach or hitting partner was caught raising four fingers at Sharapova.
Sharapova, you may be able to get away with such cheap stuff now, but it will come back to bite you sooner or later.
Or is it sooner, with the first serve woes and nagging injuries?