New York CNN  — 

Juan Martin del Potro may have been the sentimental favorite in Sunday’s US Open men’s final, but Novak Djokovic paid no attention to that on court as he beat the popular, injury ravaged Argentine to collect a historic grand slam title.

It was the latest in a string of events that could lead one to say this has been the most eventful Grand Slam ever, what with the heat, a new heat rule for the men, chair umpires intervening in play, one of the biggest upsets in tournament history and the mid-match retirement of Rafael Nadal.

Osaka prevailed against her idol 6-2, 6-4 in New York to deny Williams a record 24th major – and first as a mom – and become the first Japanese player to win a Grand Slam singles title.

The 20-year-old indeed made history for Japan but the final will be remembered as much – if not more – for Williams clashing with chair umpire Carlos Ramos in Arthur Ashe Stadium.

Ramos first gave Williams, 36, a code violation warning for coaching in the second game of the second set – he ruled that her French coach, Patrick Mouratoglou, gave her hand signals from the stands. Mouratoglou admitted in a TV interview he was coaching, though that didn’t mean his charge saw him.

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And he said his counterpart, Sascha Bajin, formerly Williams’ hitting partner, was doing the same thing.

Williams approached the net and told Ramos: “I don’t cheat. I’d rather lose. Every time I play here I have problems.”

Naomi Osaka reacts after winning the US Open, beating Serena Williams.

Williams may have been referring to the US Open in 2009, when she received a point penalty against Kim Clijsters in the semifinals – deemed to have verbally abused a linesperson – and was called for hindrance for yelling during a point in the 2011 final against Sam Stosur.

Even before then, a bad call went against Williams in the 2004 quarterfinals against Jennifer Capriati, a match that served to speed up the use of Hawk-Eye in tennis.

Point, game penalty

Williams earned a point penalty Saturday for cracking her racket when broken for 3-2 in the second and subsequently was docked a game, to trail 5-3, for what Ramos deemed to be verbal abuse towards him. “You stole a point from me and you are a thief,” Williams said during a changeover at 3-4, to prompt the ruling. Williams sought an apology from Ramos though didn’t appear to get one.

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Williams also pleaded her case to tournament referee Brian Earley and supervisor Donna Kelso, having demanded the presence of the officials on court.

Serena Williams and umpire Carlos Ramos clash during the final.

“There are men out here that do a lot worse, but because I’m a woman, you’re going to take this away from me?” Williams said. “That is not right.”

“I’ve seen other men call other umpires several things,” she added later in her mandatory news conference. “I’m here fighting for women’s rights and for women’s equality and for all kinds of stuff. For me to say ‘thief’ and for him to take a game, it made me feel like it was a sexist remark.

“He’s never taken a game from a man because they said ‘thief.’

“For me it blows my mind. But I’m going to continue to fight for women,” said Williams, before voicing her displeasure about French player Alize Cornet being told off by a male chair umpire last week for taking off her top when it was on the wrong way. Cornet had a sports bra on underneath.

On the other side of the net, Osaka didn’t know what was going on.

“It was 5-3, so I was a little confused then. But for me I felt like I really had to focus during this match because she’s such a great champion and I know she can come back from any point,” said Osaka, who wrote a report on Williams when she was in third grade.

The US Open, in a statement, said Ramos’ decision was final and not reviewable. Women’s governing body the WTA, meanwhile, released a statement in the aftermath of the brouhaha on Ashe, saying that Williams “plays with class.”

“There are matters that need to be looked into that took place during the match,” it said. “For tonight, it is time to celebrate these two amazing players, both of whom have great integrity.

“Naomi is a deserving champion and Serena at all times plays with class and makes us proud.”

Osaka sealed her first major with a thumping serve out wide. But moments later, boos rained down in tennis’ biggest stadium – it was even louder with the roof closed due to the threat of rain – as the trophy presentation was about to start.

Normally chair umpires are introduced and receive a gift, but Ramos was nowhere to be found.

Tears from Osaka

Williams urged the crowd to calm down as the 20th-ranked Osaka wept, seemingly overwhelmed by the crowd’s reaction and all the controversy.

“Let’s give everyone the credit where credit’s due and let’s not boo anymore,” Williams told the crowd. “We’re going to get through this and let’s be positive. So congratulations, Naomi. No more booing.”

Osaka, who grew up in New York, was up next in what was a difficult spot for a less experienced player: “I know that everyone was cheering for her and I’m sorry it had to end like this,” she said. She further apologized in her news briefing for stopping Williams from getting to No. 24.

“She really wanted to have the 24th Grand Slam, right,” she said. “It’s on the commercials, it’s everywhere.”

While Williams lost her second consecutive Grand Slam final – having been defeated by Germany’s Angelique Kerber at Wimbledon when first seeking to tie Australia’s Margaret Court for the all-time lead in majors – Osaka blossomed during the fortnight.

The two finalists share a laugh during the trophy ceremony.

Never before had a Japanese player won a Grand Slam singles title, with Kei Nishikori coming the closest by reaching the US Open final four years ago. Osaka also beat Williams in March in Miami, shortly after Williams returned from a 14-month layoff after giving birth to daughter Olympia.

Osaka chose to represent Japan though she could have played for Haiti – her dad is Haitian – or the United States.

Osaka now lives in Florida, a hotbed for tennis players thanks to the weather and a plethora of tennis academies.

Osaka is 16 years younger than Williams, marking the second biggest age gap in a major final after a 17-year-old Monica Seles faced the 34-year-old Martina Navratilova at the 1991 US Open.

On that day, too, the more junior player prevailed.

Osaka’s progress

Osaka has power in abundance but is also one of the best movers in the game. She has showed incredible composure as well, saving five of six break points Saturday after saving all 13 in the semifinals against Madison Keys.

Overall she dropped only one set in the tournament, which marked Osaka’s maiden Grand Slam quarterfinal.

The fans gasped when Osaka crunched a forehand passing shot winner at 4-1 and she outnumbered Williams in the “come on” stakes. A pulsating 19-shot rally went Osaka’s way when she engineered a forehand down the line early in the second.

Serena Williams (right) and Naomi Osaka line up before the women's final. It couldn't foreshadow the drama that was to come.

Williams’ normally lethal serve misfired, hitting a double fault in each service game of the first set. Williams struck back-to-back double faults when immediately broken back for 3-2 in the second, paving the way for the racket smash.

Broadway, a stone’s throw away, couldn’t match the drama that unfolded.

Undaunted, however, Osaka served the match out with aplomb, delivering a potent serve that Williams barely touched.

The US Open title was hers, but Williams and Ramos occupied the leading roles.

What on earth will happen Sunday, when Novak Djokovic and Juan Martin del Potro meet in the men’s final?