It was the infamous remark of Jean-Marie Le Pen, 88 - that the Nazi gas chambers were a "detail" of history - that landed the National Front in the political wilderness for decades.
"We need to do everything to avoid this", he added.
Macron later gave a speech in Chatellerault, western France, taking his election battle to rural areas where disgruntled farmers have increasingly shied away from politicians or turned to the far-right following years of crisis.
A former World Cup and European Championship victor, Zidane remains highly popular in France.
Le Pen said Macron supported "an ultra-liberal economy" and "total deregulation".
Despite Le Pen's painstaking attempt to "de-demonize" the party her father helped found, the National Front continues to struggle fighting off an association with anti-Semitism and Holocaust denial, the largest skeleton in a considerably cavernous closet.
Le Pen has been courting the blue-collar vote, while Macron argues that France needs to make it easier for companies to hire. "He wants to defend himself and he will be filing a legal complaint because he feels that his honour has been attacked and I can tell you that he firmly and formally contests what he is accused of".
National Front official Louis Aliot meanwhile told broadcaster BFMTV that Jalkh, a party member since 1974, meant to bring an action for defamation over the controversy that foiled his succession to Le Pen.
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Steeve Briois, another of the party's four vice presidents, would take Jalkh's place, Aliot said. Newspaper articles relayed the Holocaust-related comments he is purported to have made.
In 2015 she expelled her father from the party due to his controversial views.
He has refused to be silent as his daughter bids for power. The person conducting the interview in 2000, Magali Boumaza, a professor at Galatasaray University in Istanbul, said she retained notebooks she used at the interview, as well as a tape recording of Jalkh's comments, the Independent reported.
And while in 2002, the entire political class rallied around Le Pen's second round opponent Jacques Chirac, this time Macron has lamented the lack of a "republican alliance" to block the far-right party. "It's the first time I've heard of this rubbish", he said.
Each has served as one of the party's five vice presidents.
On Friday, Macron visited Oradour-sur-Glane in central France, where Waffen-SS troops murdered 642 people in June 1944 in the worst Nazi massacre in occupied France.
She has presented the runoff against Macron, a 39-year-old former banker who champions the European Union, ethnic diversity and free trade, as a choice between "patriots and globalists".