The 30-year-old American, nicknamed "The Black Rhino", stands between Tyson and a lucrative rematch with Britain's world heavyweight champion Lennox Lewis.
"I think Tyson is done. I'm in that one percent he can't beat," Etienne said.
"I'm not scared of anybody. He bleeds like me. He hurts like me. He has to try and get me before I get him."
The 36-year-old Tyson has not fought since being well beaten by Lewis in Memphis eight months ago.
Tyson needs an impressive victory over Etienne to spark any interest in a rematch with Lewis, 37, who also has not fought since then.
Tyson, who has a 49-4 record with 43 knockouts, also knows he has to maintain his recent good behaviour if he is to receive a licence to fight in Nevada where he has not fought since 1999.
"
I think [Tyson] should have took an easier fight, more of a sure thing
"
Clifford Etienne
But Etienne warned Tyson against looking past him to a rematch with Lewis that is tentatively planned for 21 June.
"That's a great big mistake," Etienne said. "I pose the greater challenge. For real.
"Looking over somebody, underestimating things, puts you at your weakest point.
"I think he should have took an easier fight, more of a sure thing."
Etienne, 24-1 with one draw and 17 knockouts, could do his own heavyweight prospects the power of good by beating Tyson.
He comes into the fight on the back of a draw against South Africa's Francois Botha.
"I look at it as a make or break fight," Etienne said. "It will make or break Tyson. It will make or break me."