The ATP Cup has gotten off to an awkward start with the wrong national anthem played for Moldova before their opening clash with Belgium in Sydney.
Organisers apologised to Moldovan officials after the anthem for their eastern European neighbours Romania echoed out over Ken Rosewall Arena on Friday.
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"At the start of the Moldova vs Belgium match we mistakenly played the wrong national anthem for Moldova," a statement read on ATP Cup's Twitter account.
"We are sincerely sorry and have apologised personally to #TeamMoldova."
Moldova were one of the last nations to qualify for the 24-team ATP Cup which is making its debut in 2020.
At the start of the Moldova vs Belgium match we mistakenly played the wrong national anthem for Moldova. We are sincerely sorry and have apologised personally to 🇲🇩#TeamMoldova.— ATPCup (@ATPCup) January 3, 2020
They are being led by world No.46 Radu Albot, 30, who last year became the first player from his country to win an ATP singles title by claiming the Delray Beach Open.
Albot is Moldova's highest ever ranked player while their second top ranked in Sydney is world No.818 Alex Cozbinov.
It is not the first time officials have been left red faced by an anthem gaffe at a major tennis tournament.
In 2017, Germany fumed when a banned verse of their national anthem dating back to the World War II era was sung during the opening ceremony for the Fed Cup quarter-final against the United States.
"I thought it was the epitome of ignorance. It is the worst thing that has ever happened to me," German Andrea Petkovic said at the time.
And before the 2003 Davis Cup final, Spain's pre-civil war republican anthem was played before their clash with Australia.
Spain's Sports Minister Juan Antonio Gomez-Angulo waved furiously and yelled from the stands before Australian captain John Fitzgerald was forced to apologise to the crowd afterwards.