German players were shocked when an American soloist sang a long-outdated version of the national anthem.

The U.S. may have outplayed Germany in this weekend’s Fed Cup quarterfinal, but the Americans made a major off-court gaffe.

Before Germany’s Andrea Petkovic and Alison Riske of the U.S. took the court in Hawaii, a singer inadvertently performed a long-banned Nazi-era version of the country’s national anthem.

“I thought it was the epitome of ignorance, and I’ve never felt more disrespected in my whole life, let alone in Fed Cup, and I’ve played Fed Cup for 13 years now,” Petkovic told the Associated Press. “It is the worst thing that has ever happened to me.”

The version of the anthem sung Saturday used a verse with strong nationalist messages, including the line “Deutschland, Deutschland ueber alles,” which translates to “Germany, Germany above all else.”

German coach Barbara Rittner told AFP she considered snatching the microphone from the singer.

“I could have cried, because it is always a special moment, which gives you goosebumps, when you hear the anthem being played,” Rittner said.

The USTA offered “sincere apologies” for the mistake in a statement.

“In no way did we mean any disrespect,” the statement said. “This mistake will not occur again.”

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