Actor Ashley Hinshaw’s message in an Instagram Story on Friday did not mention Masterson by name, but came one day after he was sentenced to 30 years in prison.
“To every rape victim that is that is retraumatized by witnessing society debate and focus their attention on what is going to happen to the RAPIST … I see you,” Ms Hinshaw wrote.
The comments drew praise from Chrissie Carnell Bixler, one of Masterson’s accusers, who has been critical of former That ‘70s Show actors who wrote letters of support for the actor ahead of his sentencing.
“Topher is a lucky and deserving man,” Ms Bixler wrote.
Ms Hinshaw’s remarks also drew supportive comments on her Instagram account.
“Thank you for believing survivors. I see YOU,” one wrote.
While several former That ‘70s Show cast members wrote letters in support of Masterson ahead of his sentencing, Grace has so far maintained his silence.
Fans of the popular sitcom that ran for eight seasons and 200 episodes between 1998 and 2006 have spoken in support of Mr Grace, who was the subject of rumours claiming he had been too “stuck up” to hang around with his cast mates.
“For years, Topher Grace was depicted like he was a stuck-up a**hole for not being besties with the rest of the That ‘70s Show cast, but guess who didn’t write a letter in defense of a rapist this year...” one wrote on X/Twitter.
In a letter to the sentencing judge, Ashton Kutcher described Masterson as a “role model” who was “consistently there for you when you need him”.
Mr Kutcher went on to say he did not believe Masterson was an “ongoing harm to society”.
His wife and fellow co-star Mila Kunis called Masterson “an amazing friend, confidant, and, above all, an outstanding older brother figure to me”.
“I wholeheartedly vouch for Danny Masterson’s exceptional character and the tremendous positive influence he has had on me and the people around him,” she wrote.
The couple, who married in 2015, published a video on Saturday expressing their regret for the letters after facing a widespread backlash.
“We are aware of the pain that has been caused by the character letters that we wrote on behalf of Danny Masterson,” Mr Kutcher said in the video posted to Instagram.
“We support victims. We have done this historically through our work and will continue to do so in the future,” Ms Kunis added.
Masterson was found guilty of drugging and raping two former Church of Scientology members more than 20 years ago during a retrial in November 2022. A jury was unable to reach a verdict at his first trial in 2020.