WIMBLEDON, England — The spotlight on the Australian tennis player Nick Kyrgios, whose confrontations with opponents and Wimbledon officials have made his matches can’t-miss theater for the past week, grew hotter Tuesday when news emerged that the police have begun legal proceedings against him for assaulting a former girlfriend in December.
The accusations landed on the eve of one of his most important matches, a quarterfinal showdown with Cristian Garín of Chile that he is favored to win, and less than 24 hours after he survived a five-set challenge from the American Brandon Nakashima on Monday.
That match was largely uneventful by Kyrgios standards, mostly lacking the battles with umpires, the racket smashing and even the spitting in the direction of fans that often occur when Kyrgios signs up for a tournament.
After the 4-6, 6-4, 7-6 (2), 3-6, 6-2 win Monday, Kyrgios spoke of how good he felt, how he had reached a kind of equilibrium in his life after years of turmoil and how he has been able to enjoy moments on the tennis court in a way he rarely has in the past.
“That’s probably the first time in my career where I wasn’t playing well, regardless of playing Centre Court Wimbledon, fully packed crowd, I was able to just say, ‘Wow, look how far I’ve come,’ to myself,” he said. “I was bouncing the ball before I served. I really just smiled to myself. I was like, ‘We’re here, we’re competing at Wimbledon, putting in a good performance mentally.’”
Hours later, news broke in Australia that Kyrgios had been charged with one count of common assault related to an incident with an ex-girlfriend, Chiara Passari, according to The Canberra Times and a statement from the police. Kyrgios is scheduled to appear in court on Aug. 2.
“While Mr. Kyrgios is committed to addressing any and all allegations once clear, taking the matter seriously does not warrant any misreading of the process Mr. Kyrgios is required to follow,” Pierre Johannessen, a lawyer for Kyrgios, said in a statement Tuesday evening.
Kyrgios did not register for a practice court on Tuesday, unlike the other players who have qualified for quarterfinals, including his opponent, Garín.
On Instagram, where Kyrgios is active and has posted statements during previous controversies, he posted a picture of himself speaking with a young girl at a tennis tournament and added the caption, “This is why I play 
to all my youngsters out there, believe in yourself.”
The charge against Kyrgios — he is accused of grabbing Passari during a dispute — carries a maximum penalty of two years in prison.
The charge creates an awkward situation for Wimbledon, but also the ATP, which organizes the men’s professional tour.
A spokesperson for the All England Club said Tuesday: “We have been made aware of legal proceedings involving Nick Kyrgios in Australia, and as they are ongoing, we are not in a position to offer a comment. We are in touch with Nick’s team and he remains scheduled to play his quarterfinal match tomorrow.”
The ATP in the past has waited for the legal process to unfold before penalizing a player for behavior off the court.
But it came under pressure to take action after allegations surfaced that Alexander Zverev had attacked a former girlfriend twice in hotel rooms during tournaments, even though the woman had not filed charges with the police and said she would not do so. Zverev has denied the allegations.
The ATP, which did not comment on the Kyrgios charge because, a spokesman said, the legal process is not resolved, announced last year that it was conducting an independent investigation of Zverev. The organization has not announced anything related to it other than to say it was continuing. Zverev continued to compete on the tour until he injured an ankle in a semifinal match at the French Open last month against Rafael Nadal.
Tournament officials at Wimbledon have fined Kyrgios $14,000 for two infractions this year: $10,000 after spitting in the direction of a fan after his first-round win and $4,000 fine for using an obscenity in his third-round match against Stefanos Tsitsipas.
He has also violated Wimbledon rules against having colored clothing by walking onto the court wearing — though not playing in — red sneakers and baseball caps that have been black or red.
“More attention for me,” he said Monday when asked about a potential penalty for the dress code violation. “What’s that saying? Any publicity is good publicity, right?”
