A World's Strongest Man competitor is calling for bodybuilding star Shawn Rhoden to be locked away in a pen if rape allegations are true ... with Robert Oberst telling TMZ Sports, "It pisses me off!"
"If it's f*cking true, I hope he gets his due justice," Oberst says.
Rhoden -- the 2018 Mr. Olympia -- has been accused of raping a female bodybuilder at a Utah hotel on October 12, 2018 after she had just completed a photo shoot.
Details of the incident are graphic, with officials saying the woman suffered a laceration to her genitals as a result of Rhoden's alleged actions.
Oberst -- who's shared a stage at fitness shows with Rhoden in the past -- tells us Shawn didn't seem like a guy who would commit that kind of crime ... but says if Rhoden did it, he should be punished heavily.