Serena, Naomi Osaka and the most controversial US Open final in history

Were the rules of tennis exposed during US Open final? (1:14)

Chris Widmaier details the USTA's stance on coaching during the main draw of the US Open and explains why the incident lead to the first summit for officials. (1:14)

The 2018 US Open women's final was billed as the chance to watch Serena Williams tie Margaret Court's Grand Slam singles record title at 24. The 36-year-old was a heavy favorite against Naomi Osaka, a 20-year-old upstart from Japan whose idol growing up just happened to be Williams.

One hour and 19 minutes after the match's first serve, Osaka stunned the tennis world by winning in straight sets, 6-2, 6-4. But during the trophy presentation, Osaka, who had just won her first Grand Slam title, wept openly as boos cascaded down from angry, confused fans at Arthur Ashe Stadium.

Chair umpire Carlos Ramos of Portugal had called three code violations against Williams -- the first for coaching, the second for racket abuse and the third for verbal abuse. The code violations cost Williams a point and a game, and she repeatedly clashed with Ramos, calling him "a liar" and "a thief" and saying, "I don't cheat ... You owe me an apology!" To the event referee, Williams asked, "Because I'm a woman, you're going to take this from me?"

The match pushed every button: race, gender, power and sportsmanship, fairness.

Why did this match with one of the world's greatest athletes end in such controversy? Who was most at fault? Serena? Ramos? The rules of tennis? Or some combination of the three? Since late last year, ESPN's new docuseries, Backstory, researched these questions and more. What follows is an oral history gleaned from a dozen interviews conducted for the show, which airs on ESPN's family of networks, the ESPN app and ESPN+.

The matchup: Osaka faces her idol, Serena

The year leading up to the 2018 US Open was the most tumultuous of Williams' life. In September 2017, she gave birth to her daughter, Olympia, but was bedridden for six weeks fighting life-threatening blood clots. She battled back to play at the French Open and later reached the singles final at Wimbledon, but lost to Angelique Kerber in straight sets.

Osaka, meanwhile, was on the rise after being viewed as one of the up-and-coming players on the women's tour. Earlier in the year, she won her first WTA event at Indian Wells and beat Williams in Miami the following week. At the US Open, Osaka beat Madison Keys in the semifinals to become the first Japanese woman to reach a Grand Slam final.

Christopher Clarey, New York Times columnist: [Serena] and her coach, Patrick Mouratoglou, were obviously working very hard on trying to get her confidence back. His theory is, "I want her ready to play when she's ready to win. I don't want her to go back and work her way into top form, I want her to be feeling like she's in top form when she goes to a Grand Slam or a major tournament," because, in their view, she doesn't really have the right to make an error or learn on the job. She should get ready to go. It was totally unclear to all of us, on the outside, what kind of form she'd be in coming into the US Open.

Clinton Yates, The Undefeated columnist: It's the 50th anniversary of Arthur Ashe breaking the color barrier at that tournament. If it wasn't going to be [Serena's] coronation, it was going to be Osaka's coronation. She's a young, precocious girl who has not been in the spotlight a lot. It was her first major Grand Slam. She's facing, for lack of a better term, "big bad Serena," whose whole persona was the exact growth of what we were hoping a black athlete could be.

Osaka, who was asked during her on-court interview how she managed to stave off numerous break chances against Keys: This is going to sound really bad, but I was just thinking, "I really want to play Serena." [When asked why, she said:] Because she's Serena. Like, what do you mean?

Serena Williams, in her post-semifinals match interview: It's honestly really incredible. A year ago, I was fighting for, literally, my life at the hospital after I had the baby. So, every day I step out on this court, I am so grateful that I have an opportunity to play this sport, you know? So no matter what happens in any match -- semis, finals -- I just feel like I've already won.

Osaka takes the early lead

Despite playing on the biggest stage of her young career, Osaka was poised in the first set. She broke Serena's serve twice to take a 6-2 lead.

Chris Evert, 18-time Grand Slam champion and ESPN television analyst: I thought [Osaka would] be intimidated playing in her first Grand Slam final, I thought she'd be intimidated playing Serena. ... Serena was her heroine. She came out relaxed, loose, just really out-hitting and out-moving Serena.

But during the second game of the second set, a move from Patrick Mouratoglou, Williams' coach, would spark the first controversy of the match.

An ESPN camera captured Mouratoglou repeatedly moving his hands toward him. On a split-screen video, it appears Serena was looking toward her box at the exact moment Mouratoglou was sending the signal. Chair umpire Carlos Ramos called a code violation against Williams for coaching. Under the ITF rules, it doesn't matter if a player sees their coach sending a coaching signal; all that matters is if a coaching signal is sent.

Here is Mouratoglou's explanation of the exchange:

Mouratoglou: When I do this motion [moving hands toward him], I feel as if Serena is in trouble. I feel a lot of emotion because it's such a big match for her. And I want to help, that's my job to help her. So I do a motion that she doesn't even see, actually. But that's why I do a motion. It's coaching. Yeah, it's coaching.

Question from Van Natta: It was the first time you ever sent a signal to Serena?

Mouratoglou: Yes.

Q: And you chose to do it at that moment, why?

Mouratoglou: Because I felt it was an important moment. ... It was probably one of the biggest moments of her career. She was in a Grand Slam final to equal the record of all times. And she's losing, and I feel at that moment she's lost on the court. So I try to help her. That's my job.

Serena made her case to Ramos:

After speaking to people around the game, it is clear there was some confusion over the rule.

Evert: I was just like, "What?" Patrick Mouratoglou is not known to be one of those coaches who coaches all the time. I didn't understand until they showed [the video] of Patrick -- I thought it was to go forward, to go into the net.

Palma Chryst, retired Gold Badge lines umpire: It was a clear code violation, there was no question. If [Serena] misunderstood, then she wasn't aware of the rule.

Roxane Gay, author and Yale professor: This is a woman who has been playing the game in the public eye for more than 20 years who has never cheated. So why would she be cheating now? [Ramos] should have [given Serena] the benefit of the doubt. And, all too often, black women are not given the benefit of the doubt.

Mouratoglou: Even if she saw me, that's not the problem. The question is not whether she saw me or not ... The question is: Why did all this craziness happen?

Mary Joe Fernandez, reacting to the call on air during the ESPN broadcast: So many coaches coach during matches ... the umpire never says one thing.

Norm Chryst, retired Gold Badge chair umpire, believes Ramos made the right decision: He saw coaching going on. This is the most important match of the tournament. He needs to step in if he sees something that is wrong.

Evert: I just think a soft warning from [Ramos] would have been better. Just to lean over and say, "I thought I saw coaching from Patrick, and the next time I see it, there's going to be a warning." It's such a big occasion; I just would just like [to see] a little warning [in that situation].

Norm Chryst: I did over 4,000 matches and I likely gave 25-50 code violations for coaching. [He said he did let many instances slide, but added he thought the Serena example was different.] In that environment, in that match, I don't think [giving a slide is] the right thing to do. I don't think you can be soft in a US Open final with that many people watching.

Williams seemed to use the coaching call controversy as jet fuel in the next game, playing far more aggressively and attacking the net. After she went ahead 3-1, Serena had a conversation with Ramos during the break that was important in understanding what would follow:

The final unravels ...

After Osaka broke back against Serena's serve to make it 3-2 in the second set, Serena smashed her racket after losing the game on an unforced error. It led Ramos to call a second code violation against Williams for racket abuse; combined with the previous call for coaching, the second code violation cost Williams a point in the following game, putting Osaka up 15-0. But Serena did not hear the initial announcement of the second call from Ramos.

Pam Shriver, Hall of Fame doubles champion and ESPN television analyst: The state of mind that Serena was in, given the acoustics of the stadium, she didn't hear the 15-0 ... that was really one of the many disjointed parts of the controversy -- that Serena thought the racket break was the first code violation, so it would have just been a warning; instead, it was a point.

As Serena walked back onto the court after the break, she heard Ramos call out "15-love," and approached the umpire chair asking why:

Mouratoglou: She felt humiliated because she felt like he was basically saying that she was cheating, and that's the worst thing you can say to Serena. She prefers to lose 100 times than people to think she's cheating.

Palma Chryst: If she misunderstood, then she wasn't aware of the rule, or she didn't know that a code couldn't be rescinded.

Osaka held serve to even the set and then broke Williams' serve in the following game to take a 4-3 lead. During the break, Williams had another exchange with Ramos from her chair, this one more contentious than the initial conversation over coaching:

S.L. Price, Sports Illustrated: She called him a liar and you can see in the footage -- he looks away, he takes it. I don't know about you, but being called a liar is a pretty big slap in the face.

Yates: When you watch the interaction between the chair umpire and Serena, it's one that -- how do I explain this? -- if you've been in scenarios in which, as a black person in America, your identity is being confronted and taken from you, there is a flight-or-fight reaction that forces you to behave in a way that sometimes people don't recognize as reasonable. That is understandable from any point of view of an African American in this country.

Mouratoglou: [Ramos'] job is also to keep the match under control. He totally lost control of the match, completely, because he reacted with emotions. And he's not supposed to -- he's a chair umpire, he's not a player.

Palma Chryst: I thought he handled the situation really well. He was calm, I thought he listened to her.

Shriver: When you get called a liar and a thief in a US Open final, when all that happened, [Ramos] had a choice -- he could have let it go, somehow gotten her to calm down and get ready to play. ... But he made the choice of verbal abuse. This was the third of the code of conduct violations. It was also the second one, to me, where Ramos could have gone either way with it.

Ramos' ruling was another code violation, Williams' third of the match, which cost her a game and put Osaka ahead 5-3 in the second set. After initially challenging Ramos, Williams called for the referee.

Shriver: And it was again the same two, [WTA supervisor] Donna Kelso and [US Open tournament referee] Brian Earley, who walked out on the court just like they had at other times during controversial situations with Serena at US Opens. It was like déjà vu. I think [Williams] had a flood of past memories, bad memories, on that court. And you could hear it: "Why does this always happen to me here? It's happening to me again."

Price: There are many people and, I would be among them, who would tell you that, yeah, men have said much worse things on court to officials than even "thief." Jimmy Connors, the much-celebrated Jimmy Connors, the 39-year-old hero of working-class people everywhere, during [that 1991 US Open run] repeatedly called a chair umpire "an abortion," and didn't suffer any penalty whatsoever. Now, I don't know about you, but that would be right up there with "liar" or "thief" for me.

Controversy reigns: 'I am sorry it had to end like this'

Behind Serena's 2018 US Open drama

In an excerpt from ESPN's Backstory, Clinton Yates explains what might have spurred the verbal altercation between the chair umpire and Serena Williams in the 2018 US Open final.

Osaka won 6-2, 6-4, becoming the first Japanese woman to win a Grand Slam title. Williams hugged Osaka at the net but refused to shake hands with Ramos, saying to him twice, "You owe me an apology."

Mouratoglou, in a postmatch interview with Pam Shriver during the original ESPN broadcast: I'm honest, I was coaching. I don't think she looked at me, so that's why she didn't even think I was. I was like 100% of the coaches on 100% of the matches, so we have to stop this hypocrite [rule]. Sascha [Bajin, then Osaka's coach,] was coaching every point, too. This chair umpire was the chair umpire of most of the finals of Rafa [Nadal], and Toni's [Nadal, Rafa's coach and uncle] coaching every single point and they never gave a warning. I don't really get it.

The trophy celebration was overpowered by overwhelming boos from the crowd, leading Osaka and Williams to tears.

Price: What should have been triumph [for Osaka] was a real travesty.

Katrina Adams, CEO of the USTA, speaking to the players during the postmatch trophy presentation: These two weeks, you two have shown your power, your grace and your will to win. Perhaps this was not the finish we were looking for today, but Serena, you are the champion of all champions. This mama is a role model and respected by all.

Some interpreted Adams' comments as implying she wanted Williams to win the title. Chris Widmaier, managing director of corporate communications for the USTA, said that was not the case. Though Adams declined ESPN's interview request, Widmaier said it was meant to mean the match should have been "a celebration, but it was not." Widmaier also agreed with Ramos' decision to call the initial coaching violation. "It seemed like a very blatant signal to all of us."

Osaka addressed the pro-Williams crowd during the ceremony: I'm sorry. I know that everyone was cheering for her, and I'm sorry that it had to end like this. I just want to say thank you for watching the match. Thank you. ... It was always my dream to play Serena in the US Open finals, so I'm really glad that I was able to do that. I'm really grateful that I was able to play with you. Thank you.

Williams was ultimately fined $17,000 for the three code violations -- $4,000 for receiving coaching, $3,000 for racket abuse and $10,000 for verbal abuse. Within days after the match, the International Tennis Federation released a statement supporting Ramos' calls.

The postmatch debate

Serena vs. the umpire fantastic for tennis

Serena Williams' coach Patrick Mouratoglou admits that the controversy between Serena and the chair umpire drew fans to tennis.

The conversation around the final continued for days. Talk show hosts in sports and news spaces took sides, and the debates went beyond tennis.

Whoopi Goldberg, co-host of ABC's "The View" on a September broadcast: What bothers me is, it was sexist. Even John McEnroe said it was sexist.

Stephen A. Smith, on ESPN's First Take: Serena Williams was wrong. Somebody has to say it, so I will.

Billie Jean King, from one of her postmatch tweets on Sept. 8, 2018: When a woman is emotional, she's "hysterical" and she's penalized for it. When a man does the same, he's "outspoken" & there are no repercussions. Thank you, @serenawilliams, for calling out this double standard.

Roxane Gay: I understood it was so much more than that moment, I felt like it was a career of having to defend herself. People have very narrow perceptions of black women as angry and as violent, and I think Serena is often framed that way. I love when someone is excellent and unapologetic about their excellence and clearly invested in their ambitions. And she does all of those things and she models for young girls and women what excellence can be and how it's OK to strive for the things that you want.

Ramos, who declined interview requests from ESPN, reportedly received messages of support from family, colleagues, players and former players after the incident. He avoided social media and did not go out the day after the final to avoid problems.

Ramos, who is from Portugal, spoke briefly to Portuguese newspaper Tribuna Expresso the week after the match: "I'm fine, given the circumstances. It's a delicate situation, but umpiring 'a la carte' doesn't exist. Don't worry about me."

Because of the incident, the USTA held the first global summit for officials, a two-day meeting where improving the training for umpires was discussed. The USTA is also creating a centralized video hub with feeds to monitor all umpires' calls. The videos will also help with better messaging to the public on why certain calls have been made.

The USTA had submitted a proposal earlier this year to the International Tennis Federation and Grand Slam board that would allow coaching at the US Open (it is allowed on the WTA Tour, not the Grand Slams). Both organizations declined it, forcing the USTA to pull its plan.

The last word: 'It was great for tennis'

Though Evert and others said the match was bad for tennis, and an indication that the rules of the game failed everyone involved, Mouratoglou had a different final take:

Don Van Natta Jr. is the host and co-executive producer of the new ESPN series "Backstory" and a senior writer for ESPN. Email him at Don.VanNatta@espn.com or follow him on Twitter @DVNJr.