Tetchy accusations of lying dominated the final televised presidential debate in Austria between far-right candidate Norbert Hofer and former Greens leader Alexander Van der Bellen last night.
Polls show them neck-and-neck for Sunday's vote.
A Hofer victory would make him the first far-right head of state in the European Union.
Mr Van der Bellen narrowly won a run-off vote in May, which was annulled due to poor counting.
After almost a year of campaigning, the two candidates, who have left centrist rivals far behind, showed clear signs of losing patience with each other, making accusations ranging from endangering Austria's economy to espionage.
"I get it, you were nothing," Mr Hofer said to Mr Van der Bellen, who is running as an independent candidate, rhetorically taunting him about his previous role with the Greens and accusing him of having been a Communist.
"You're lying again!" Mr Van der Bellen replied.
After Mr Hofer accused him of having been a spy, he said: "This is the meanest thing I've experienced in a long time ... This is ridiculous."
Mr Hofer said Mr Van der Bellen had told lies about his stance on civil service and conscription laws as well as Austria's neutrality.
"This is another falsehood," Mr Hofer said.
The moderator on public broadcaster ORF tried to force the candidates to focus on their policies, but both read out loud repeatedly from big folders full of printouts of contentious quotes by the other and aggressive Facebook posts.
After a Freedom Party official had implied on television that Mr Van der Bellen's father might have sympathised with Nazi fascism, the independent candidate rejected such allegations and produced a photo of his father, who died 50 years ago.
Mr Hofer described this move as a "bad foul" and called on his rival to stop "wanting to inspire pity", adding some of Mr Van der Bellen's supporters had also called him and his father a Nazi.