Talk about a costly mistake. 

A restaurant in New York City accidentally gave a $2,000 bottle of wine to a couple who had ordered an $18 bottle, according to the restaurant’s owner. 

Keith McNally, the owner of Balthazar, posted about the mistake on Instagram on Wednesday. It is unclear when exactly the event took place.

According to the post, the incident began when four businessmen ordered a $2,000 bottle of Chateau Mouton Rothschild, Balthazar’s “most expensive red wine.”

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After the businessmen ordered their wine, a manager poured the bottle into a decanter at a waiter’s station. 

Around the same time, a couple ordered an $18 bottle of Pinot Noir -- the cheapest red wine option at Balthazar -- and another manager poured that bottle into another, identical decanter. 

When the first manager returned, he mistook the Pinot Noir for the Rothschild and “formally poured the cheap wine to the businessmen,” the post said. 

“According to the manager, the host considered himself a wine connoisseur, and showing off to his guests, tasted the cheap wine before bursting into raptures about its 'purity,’” McNally wrote.

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Meanwhile, the couple who had ordered the Pinot Noir was being served the $2,000 bottle of wine.

“On taking their first sips of what they believed was cheap wine, they jokingly pretended to be drinking an expensive wine and parodied all the mannerisms of a wine snob,” McNally wrote.

However, the managers soon realized their mistake and called McNally, who hurried to the restaurant from his house.

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When he arrived, he said he found himself in a predicament. 

“The businessmen's celebratory mood was clearly enhanced by the wine they had mistakenly thought was the restaurant's most expensive,” he wrote. “This put me in a dilemma: whether to come clean and admit the manager's mistake, or allow him [sic] to continue drinking the cheap wine in blissful ignorance.”

A couple dining at Balthazar in New York City ended up drinking a bottle of $2,000 red wine after managers mixed it up with the $18 bottle they ordered. (iStock)

He said it would also be “unthinkable at this point” to take back the $2,000 bottle of wine from the couple, who were also enjoying their evening.

“I decided to veer from my normal behaviour [sic], and tell both parties the truth,” he said. 

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According to his post, one of the businessmen said he had suspected the wine wasn’t a Rothschild, while the others “nodded their heads in servile agreement.” 

Meanwhile, the couple was “ecstatic by the restaurant’s mistake,” and they told him “it was like the bank making an error in their favour [sic].”

“The trouble was, it was me who was down $2000, not the bank,” McNally wrote. 

He ended his post by saying: “Both parties left Balthazar happy that night, but the younger of the two left happier.”

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McNally also owns Balthazar in London and the Balthazar Bakery in New Jersey.

Aside from Balthazar, his New York City restaurants include Pastis, Morandi and Minetta Tavern, according to his Instagram account.

McNally also used to own at least two other New York City restaurants -- Lucky Strike and Augustine -- but both have closed because of the coronavirus pandemic. 

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