The 20-year-old breakout star of the tournament swept into the record books and Saturday's championship match against the 23-time major victor with a 6-2, 6-4 win over Madison Keys, the runner-up in 2017.
A relatively calm conversation on a changeover seemed to settle things down, but Williams was further infuriated when she was docked a point for a second violation after smashing her racquet in frustration at dropping serve, calling chair umpire Carlos Ramos a "thief".
Continuing her argument with Ramos at the change of ends, Williams accused him of being a thief for taking a point away from her.
And after the pro-Williams Arthur Ashe Stadium crowd had showered Osaka and chair umpire Carlos Ramos with boos for a controversial game penalty, the youngster was asked why she thought to apologize for her victory.
"You will never, ever, ever be on another court of mine", she fumed. But Williams played a poor game right after that to get broken immediately, and she smashed her racket on the court, destroying it. It all dates back to 2004, when an incorrect call during a quarterfinal loss to Jennifer Capriati was cited as the main reason for the introduction of replay technology in tennis. "That's, I think, one of the key issues we'll be talking about moving forward".
Williams hasn't won the U.S. Open since 2014 and hasn't won anywhere since the 2017 Australian Open, when while pregnant she became the oldest Grand Slam female champion at 35. "Maybe it was the mom in me that was like, Listen, weve got to pull ourselves together here".
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.
While Brennan says Osaka deserved the win, she also believes Serena's punishment is one the major concerns of this year's match.
South and North Korea in high level talks for summit
Moon and Kim have since agreed to hold a third summit in Pyongyang at an unspecified date in September. "Now is a very important period in settling peace on the Korean Peninsula".
Billie Jean King, the namesake of the tennis center where the U.S. Open is now played, fought for prize parity in the '70s.
Osaka had given Williams plenty of respect but no other concessions as she grabbed the early break on a double fault by her idol for a 2-1 first set lead that she would not let go.
Williams said she didn't know if she would have managed to turn things around if the dispute with Ramos had not occurred.
"I had an opportunity to do that this summer, and it didn't happen, so I'm just going to keep trying", said Williams.
"I don't want to be rude", Williams said in an ESPN post-interview.
Osaka was born in Japan but left when she was three years old and raised in the United States. Like, (Alizé) Cornet should be able to take her shirt off without getting a fine.
Both Williams and Osaka likely wish the officiating had gone a bit differently on Saturday, but thankfully, there's little doubt that these two will meet again on the court in a critical match in the near future.
"I just feel like the fact that I have to go through this is just an example for the next person that has emotions, and that wants to express themselves, and wants to be a strong woman. I should just try to play her as an opponent". "I wasn't being coached".