´óÏó´«Ã½

Alexander Zverev says he is taking legal action over allegations he abused his former girlfriend and issued a statement to "categorically and unequivocally deny" the claims again.

The German world number four last year denied Olya Sharypova's allegation he was violent towards her and he repeated that on Friday after new details of her accusations were published this week.

Three days before the US Open, where he is among the favourites, he also backed calls for governing body ATP to introduce a domestic violence policy.

"I have engaged my German and American lawyers in the matter. They have already obtained a preliminary injunction against the source and the author who published the false allegations," Zverev wrote in a statement posted on Twitter.

"The lawyers have therefore initiated further proceedings against the source and the author.

"I categorically and unequivocally deny having abused Olya."

The latest allegations were published on Slate - an online magazine.

Katie Rayford, Slate's spokesperson, said: "Today we were informed that Alexander Zverev started legal proceedings in Germany against Slate following our report on alleged domestic abuse. Though Slate does not comment on pending litigation, we stand by our fair and accurate reporting."

Last year Britain's Andy Murray joined world number one Novak Djokovic in urging the men's tennis governing body, the ATP, to introduce a policy on domestic abuse following the allegations made against Zverev.

"I also fully support the creation of an ATP domestic violence policy," Zverev said.

"I will not address this matter any further."

Zverev is the fourth seed at Flushing Meadows and on a good run of form, having won Olympic gold and the Cincinnati title this month.