Nana Kwaku Bonsam predicted in February that the 28-year-old would miss the World Cup through injury, most importantly missing Portugal's group game against Ghana.
And the FPF revealed on Tuesday that Ronaldo was undergoing "specially adapted, individual" training as he bids to shake off a knee problem before their opener against Germany on June 16.
"I know what Cristiano Ronaldo's injury is about, I'm working on him," Bonsam said in an interview with Angel FM.
"I am very serious about it. Last week, I went around looking for four dogs and I got them to be used in manufacturing a special spirit called 'Kahwiri Kapam'".
Bonsam - whose name translates as 'Devil of Wednesday' - insists Ronaldo, at the very least, will not feature in the group stages.
"I said it four months ago that I will work on Cristiano Ronaldo seriously and rule him out of the World Cup or at least prevent him from playing against Ghana and the best thing I can do is to keep him out through injury.
"This injury can never be cured by any medic, they can never see what is causing the injury because it is spiritual. Today, it is his knee, tomorrow it is his thigh, next day it is something else."
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