LONDON -- German tennis player Alexander Zverev will not face disciplinary action after an investigation into domestic abuse allegations against him found "insufficient evidence" to substantiate the claims, the men's professional tour said Tuesday.
The ATP had commissioned the investigation in October 2021 after Zverev's former girlfriend, Olya Sharypova, accused the 2020 U.S. Open runner-up of abuse.
"Based on a lack of reliable evidence and eyewitness reports, in addition to conflicting statements by Sharypova, Zverev and other interviewees, the investigation was unable to substantiate the allegations of abuse, or determine that violations of ATP's On-Site Offenses or Player Major Offenses rules took place," the ATP said in a statement.
Zverev, who won the singles gold medal at the Tokyo Olympics, has always denied the accusations. The 25-year-old player is currently ranked 14th.
Although no disciplinary action will be taken, the ATP said it would reevaluate the determination "should new evidence come to light, or should any legal proceedings reveal violations of ATP rules."
The 15-month investigation was conducted by Illinois-based Lake Forest Group and included interviews of more than two-dozen people and reviews of text messages, audio files, and photos submitted by Sharypova and Zverev.
"This included materials voluntarily extracted from Zverev's electronic devices via a third-party forensic expert,'' the ATP said.
The investigation looked primarily into accusations of abuse at the ATP Masters 1000 event in Shanghai in 2019 but also included "purported misconduct in other locations, including Monaco, New York and Geneva, as referenced in public reporting.''
Ultimately, investigators "found insufficient evidence to substantiate published allegations of abuse," the governing body said.
ATP CEO Massimo Calvelli said turning to specialist investigators was "new ground'' for the tour.
"We ultimately believe the exhaustive process was necessary to reach an informed judgement,'' he said in a prepared statement. "It has also shown the need for us to be more responsive on safeguarding matters. It is the reason we've taken steps in that direction, with a lot of important work still ahead.''
Zverev lost to Michael Mmoh in the second round of the Australian Open earlier in January.