Novak Djokovic backed the idea of tennis developing a domestic violence policy following allegations made against Alexander Zverev.
The German's season ended with a 6-3 7-6 (4) loss to Djokovic at the Nitto ATP Finals, sending the world number one through to a semi-final clash against US Open champion Dominic Thiem on Saturday.
Zverev has been competing under the considerable shadow of serious abuse claims made by his ex-girlfriend Olga Sharypova.
"I sincerely wish for him that he overcomes this soon and that he can focus on his life and tennis career."
Zverev again implied he would not be taking legal action – something Sharypova has also said – and, despite the allegations and the coronavirus pandemic, declared it had been a "great year".
The 23-year-old said: "Unfortunately I lost a lot of big matches. I lost semi-finals in Australia, which I could have won. Lost the final of the US Open, which I should have won. Finals in Bercy (the Paris Masters). This match here.
"The US Open match obviously still hurts, but all the other ones, it's great that I'm playing at this level again."
Djokovic's victory means the four top seeds have all reached the semi-finals for only the second time since 1990, with Rafael Nadal taking on Daniil Medvedev in the other last-four clash at London's O2 arena.
Djokovic, who is chasing a record-equalling sixth title, still was not at his best but played, and fought, a lot better than in his convincing loss to Medvedev on Wednesday.
He won the first seven points of the match and then withstood everything Zverev threw at him in the second set before playing a near-flawless tie-break.
Djokovic has beaten Thiem in seven of their 11 meetings but the Austrian came out on top in London last year and in the French Open semi-finals before Djokovic gained revenge in a five-set Australian Open final.
"I have lots of respect for Dominic, his game, his work ethic," said Djokovic. "Every time we got to play in the last three or four matches, it was some marathon, thrilling encounters.
"It's semi-finals so I'm expecting a tough battle. He's in very good form. He loves to play on this surface. He played finals last year, beat Roger (Federer) and myself.
"He's a grand slam champion, obviously that's a huge boost for him. If I manage to play as well as I did today and show up with a high quality of tennis, I think I have a good chance to win. I'm just hoping I can start off the match as well as I did today."
