Tonioli revealed that the judges could still turn nasty on the final three celebrities if their freestyle routines are not up to scratch and said that former contestants had lost out on the Glitterball trophy because of errors in the showdance.
"The dreaded freestyle. If they get that wrong, the judges can turn. The judges can still turn!" the Italian told It Takes Two.
"If someone fails badly, like Colin Jackson did one year, it can cost you. It's not something that you can just throw away."
Jason Donovan, Harry Judd and Chelsee Healey will battle it out on Saturday night for the Strictly 2011 crown.
Building up the final, Tonioli said: "They are all brilliant. They have all done so well. It's going to be an incredible final. They are all so fabulous. It's going to be spectacular."
He described Healey as a "natural," claimed Donovan delivered an "Oscar performance" with his Argentine tango and argued that there was no-one in the country "that wasn't moved" by Judd's Viennese waltz routine.
The Strictly Come Dancing final airs Saturday, December 17 at 7pm on BBC One.
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