Maria Sharapova is a "cheater" and should not have been allowed to return to tennis, says 2014 Wimbledon finalist Eugenie Bouchard.
The Russian won her first match after a 15-month doping ban on Wednesday, beating Roberta Vinci 7-5 6-3 in the first round of the Stuttgart Open.
She was controversially given a wildcard for the tournament.
Five-time Grand Slam winner Sharapova was suspended last March after testing positive for meldonium.
"She's a cheater and I don't think a cheater in any sport should be allowed to play that sport again," said Canadian Bouchard.