Klasnic and Terry were involved in a heated exchange during England's 5-1 win over Croatia at Wembley on Wednesday night and, after his country secured their place at the World Cup finals, the England defender claimed that his opponent had spat at him.
But Klasnic, who joined Bolton on loan from Nantes on transfer deadline day, refutes the accusation. The 29-year-old had a double kidney transplant in 2007 and has now accused Terry of hitting him in a sensitive area.
"He hit me with a fist exactly in the place where I've been operated," Klasnic told the Sun. "I was lucky to be wearing a protective belt. He is the first player who has tried to hit me with a purpose in the kidney. He insulted me first then he hit me.
"And now he has accused me of spitting at him? I didn't do it. We spoke after the final whistle and I thought we sorted everything out - but obviously not so."
Klasnic is yet to make his debut for Bolton and Trotters manager Gary Megson hopes that the early controversy to surround his new arrival will be quickly forgotten.
"Ivan told me he has spoken with Terry and they have had a private word and the matter is between them," Megson said. "It was private so I don't know what was said but, as I understand, it has been sorted."