Tennis’s highest-ranking official has received a 12-month suspension for unethical conduct and abuse of power, the Telegraph can reveal.

The umpiring scandal involves US Open referee Soeren Friemel, the man who ruled on Novak Djokovic’s expulsion from the 2020 US Open. Friemel – a German in his early 50s – has been mostly absent from tournaments since the build up to last year’s Wimbledon, supposedly for “personal reasons”.

But the Telegraph has learned that Friemel entered voluntary suspension on June 19 after a younger male umpire made serious allegations about his behaviour.

A five-month investigation ensued, undertaken by an independent QC. The 12-month suspension was handed down in December, but it was only after an unsuccessful appeal that Friemel’s sentence was finally reconfirmed by a panel on Monday. Friemel has been contacted for comment.

“The complaint was that Soeren made inappropriate comments and invitations to an individual,” said a spokesperson for the International Tennis Federation, which has employed Friemel as its head of officiating since 2014. “The issue was the situation of power imbalance, which led the investigating officer and the panel to find a breach of the code”.

Four different instances were brought to the attention of tennis’s governing bodies in May 2021. These instances occurred between 2011 and 2015, and all involved the same younger male umpire. The investigation involved interviews with multiple sources.

The panel found that Friemel had broken three clauses of the Joint Certification Programme Code of Conduct. The two key paragraphs are Article 13 –which states that “Officials shall not engage in unfair, unprofessional, criminal or unethical conduct” – and Article 14: “Officials shall not abuse his/her position of authority or control, and shall not compromise the psychological, physical or emotional wellbeing of other Officials, players or tournament personnel.”

Asked whether the ruling would affect his position at the ITF, the spokesperson replied that “Soeren remains under suspension and we are reviewing our course of action.”

One odd wrinkle in this case was that Friemel turned up at the US Open for qualifying week in late August. He was described by one perplexed observer as “hanging out in the referee’s office as if nothing was going on”. But he left on the eve of the first main-draw matches, and an article then appeared in the Washington Post reporting that he “needed to leave for personal reasons”.

The panel decided that the four days Friemel spent at the US Open would not affect the date of his return. His year-long suspension has been backdated to June 19, 2021, and will thus end at midnight on June 18.

In theory, this would allow Friemel to work at Wimbledon this year in his customary role as a grand slam supervisor – one of a group of senior officials who step in when there is an incident on the courts.

However, Wimbledon always choose their own officials, after discussions between referee Gerry Armstrong, chief umpire Adrian Wilson and tournament director Jamie Baker. It is understood that they prefer to use officials who have been working recently at other tournaments, which might well count against Friemel.

The most visible moment of Friemel’s officiating career came at the 2020 US Open, a year after he had inherited the referee’s role from Brian Earley. After Djokovic had whacked away a loose ball which happened to fly into the throat of line judge Laura Clark, Friemel spent ten minutes speaking to him on the court. The players then shook hands and the match was awarded to Djokovic’s opponent Pablo Carreno Busta.