The 43-year-old Slipknot frontman thinks the "I Love My Life" hitmaker is "amazing", and has revealed he has penned a track for his unlikely idol.
Although the heavy metal rocker said he has probably "lost cool points" for admitting to liking the 42-year-old British singer, reported Contactmusic.
"I actually wrote a song for Robbie Williams. I love Robbie. He's amazing. He cracks me up. He's a great entertainer, he's an amazing singer. And I just love the energy that he's got.
"I know that I'll probably lose cool points with a few people for that, but I just love him. I think he's great.
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