NEW YORK (Kyodo) -- Naomi Osaka wrote her name in Japanese sporting history on Saturday, becoming the country's first singles Grand Slam champion by beating Serena Williams 6-2, 6-4 in the U.S. Open final.
In the players' second meeting, Osaka kept her record unblemished against the woman regarded by most as the best-ever, dominating the first set and then overcoming a 3-1 deficit in the second to deny Williams a record-equaling 24th Grand Slam trophy.
But it will be a huge umpiring controversy that will grab the headlines.
Williams was handed a "game penalty" after arguing with the umpire and calling him a "thief" after he took a point away for receiving coaching from her box.
It was a moment that turned the match and a controversy that put something of a dampener on Osaka's win as boos rained down on the court from the partisan Flushing Meadows crowd.
The 20-year-old Osaka's win came in her first Grand Slam final and is her second on tour after she claimed her debut tournament title at the 2018 BNP Paribas Open.
"I know that everybody was cheering for her. I'm sorry it had to end like this. I just want to say thank you for watching the match," said Osaka, the youngest woman to reach a Grand Slam singles final since Caroline Wozniacki in 2009.
When questioned about how hard it was to play through the situation, both at the other end of the court and with an unhappy and vocal crowd, Osaka was clearly upset.
"It was kind of difficult because I was really concerned about her, like, the inner fan in me jumped out, so I really had to push to keep a straight face."
"It feels very emotional, I feel a bit happy and sad at the same time. I think this is the most I have ever cried," said Osaka who was comforted by Williams as tears rolled down her face during the trophy presentation.
Williams, who also was in tears during and after the match, tried to ensure the moment was not ruined for Osaka, a player who idolized her when she was growing up.
"(Osaka) played well, this is her first Grand Slam. I know (the crowd) were here rooting. Let's make this the best moment we can. Let's not boo anymore. We're gonna get through this and we're gonna be positive. No more booing," she told the crowd.
In the press conference later she was still fuming.
"I've seen other men call other umpires several things, and I am here fighting for women's rights and women's equality and for all kinds of stuff and for me to say 'thief' and for him to take a game it makes me feel like it is sexist."
"This is outrageous. I just feel like that I have to go through this (and) it is just an example for the next person that has emotions and who want to express themselves and want to be a strong woman. They are going to be allowed to do that because of today, maybe it didn't work out for me, but it is going to work out for the next person."
Osaka dropped just one set on her way to the tournament win, and kept intact a 32-0 record of victories this season when she won the first set.
Despite the age and experience difference -- Osaka is 16 years Williams' junior -- it was the American who opened the match looking the more nervous.
Both players held their opening service games, but then Osaka turned the screws, earning one break point in each of Williams' next two service games, winning both while holding her own serve to build a 5-1 lead. Williams won one more service game, but Osaka closed out the set.
Williams' first set was plagued by errors, finishing with 13 unforced errors, four double faults and just a 38 percent first serve rate.
At the other end of the court, Osaka could do no wrong. In addition to taking both her break point chances, she was nearly untouchable on her own serve, winning 18 of 26 points, including two by ace.
In the second set, stats would not matter.
Osaka gave up her first service game of the second set, and then went down 3-1 by dropping her second, but then turned the match on its head by breaking immediately back and then holding to draw even in the set at 3-3.
While serving at 3-3 Williams argued with the umpire who had ruled multiple times she was receiving coaching from her box.
Williams called the umpire a liar, saying she has "never been coached," then called him a "thief, too" after he docked her a point.
Under fire from Williams, the umpire handed her the game penalty advancing the score to 5-3 in Osaka's favor and leaving the American serving to stay in the match.
Williams held, but Osaka was able to do the same in her next service game to win the set and the match.
After the game, Williams' coach Patrick Mouratoglou said, "I was coaching...like 100 percent of coaches 100 percent of the matches." He said the situation should have been avoided, particularly in the final of a Grand Slam.
Williams, however, said she does not know why Mouratoglou said he was coaching from the stands.
"I texted Patrick (to ask) what is he talking about. We don't have signals, we've never discussed signals. I don't even (normally) call for on-court coaching. I don't understand why he would say that."
Earlier in the day Japan's wheelchair tennis ace Shingo Kunieda beat Nicolas Peifer 2-6, 6-4, 7-5 to claim his seventh U.S. Open title.
He added the 2018 U.S. Open title to nine Australian Open and seven French Open tournament victories, as well as two Paralympic gold medals.