Redemption for Japan's Kato with French Open mixed doubles title
The pair rallied to beat Canada's Bianca Andreescu and New Zealander Michael Venus 4-6, 6-4, (10-6) in the final on Court Philippe Chatrier.
Kato and her Indonesian partner Aldila Sutjiadi had been disqualified from the women's doubles competition in the third round earlier in the week against Czech Marie Bouzkova and Spain's Sara Sorribes Tormo.
Kato hit a ball down the court between points, inadvertently striking a ball girl. Chair umpire Alexandre Juge handed Kato a warning but Bouzkova and Sara Sorribes Tormo pointed out that the ball girl was sobbing.
After speaking to the girl, the umpire went back up to his chair and announced the disqualification of Kato and Sutjiadi, leaving the Japanese player in tears.
Kato, who said on Twitter later that she was penalised by Roland Garros and forfeited her prize money and points for the women's doubles competition, received plenty of backing from her fellow players.
"It's been challenging mentally after the disqualification. I want to thank everyone for the heartfelt messages of support," Kato said in her prepared speech after the final.
"I was able to use all the positive energy so I could be here today. Thanks to Aldila and all the Indonesian fans. I'm doing my best so we can one day return and claim the women's doubles title.
"To Sara and Marie, Aldila and I hope we can play each other again somewhere and have a great match.
"Lastly to Roland Garros, it's unfortunate about the disqualification. But I'm looking for a positive outcome for my appeal. So I can receive my points and prize money."
The Professional Tennis Players Association (PTPA), which has 22-time Grand Slam champion Novak Djokovic on its executive committee, said the decision to default Kato and Sutjiadi was "unjustifiably disproportionate" and "unfair."