Sascha Bajin, Naomi Osaka's former coach, said he had a dream the night before the 2018 US Open that a controversy would take place. (Photo by Koji Watanabe/Getty Images)

Sascha Bajin could have warned us. Then again, what’s the fun in that.

Bajin spent the night before the 2018 U.S. Open in restless sleep as he worried about what Serena Williams might throw at Naomi Osaka, the young star he coached from November 2017 to February 2019.

We all know now what occurred at Arthur Ashe Stadium in Flushing, New York. Osaka won her first Grand Slam title in a match filled with controversy as Williams got into it with chair umpire Carlos Ramos.

Bajin, to an extent, knew then.

Bajin dreams of 2018 US Open controversy

Bajin told espnW’s D’Arcy Maine in a piece published Wednesday that he saw a controversy with Williams taking place in back-to-back nightmares the eve of the final. The other nightmare, he told espnW, was about drama with Williams’ longtime coach, Patrick Mouratoglou. Both took place at Arthur Ashe Stadium in his dreams and in real life.

"The funny thing is, I don't believe in epiphanies, and I'm not very spiritual," Bajin said during a rare break at last week's Western & Southern Open in Mason, Ohio. "But I was a total mess in the morning, and I looked like a zombie because I really just hadn't slept. I wanted to keep everyone calm and focused, and I didn't want to be the guy to come down and say, 'You're not going to believe the dreams I just had, and here's what I know,' but I did tell Naomi's mom, and some friends of mine, about them."

Bajin, who worked for several years with Williams as her hitting partner, said he was shocked just as everyone else was at the events unfolding, but had to “trust in [Osaka] as a player” and couldn’t do much.

Williams lost the first set and took a 3-1 lead in the second when chair umpire Carlos Ramos issued a warning for a coaching violation from Mouratoglou. He did it again six games later and Williams tore into Ramos by saying “I don’t cheat to win, I’d rather lose.” She was adamant there was no coaching and insisted on an apology. Ramos penalized her a game.

The nightmare about Mouratoglou spilled out afterward. Williams insisted her coach gave her a thumbs-up that Ramos interpreted as a signal, which set off the initial warning. Mouratoglou acknowledged afterward he tried to signal her, but doesn’t think she saw him. It’s an open secret that’s done in both men’s and women’s tennis, anyway, and the motives behind a Grand Slam final warning for it were questioned.

Williams, Osaka return for 2019 US Open

Williams and Osaka will be back at the U.S. Open beginning Monday. Osaka is the draw’s top seed and Williams earned a No. 8 seed. Ramos will not be officiating matches involving Williams or her sister, Venus, the U.S. Tennis Association announced.

“We want the attention of the competition to be on the athletes,” USTA executive Stacy Allaster said.

Earlier this summer, Williams penned a heartfelt letter to Osaka apologizing for how everything happened and giving her support, which began at the award ceremony. They faced off for a third time earlier this month with Williams taking her first win against the 21-year-old who calls the veteran her “tennis mom.”

“I’d say more or less tennis grandma. That was very kind of her to say mom,” Williams said.

Osaka parted ways with Bajin, 34, in February after more than a year working together. Starting in November 2017, the duo experienced titles at Indian Wells, the U.S. Open and the Australian Open, and Osaka moved up to world No. 1. He was named the WTA’s first-ever coach of the year for 2018.

Bajin did not comment on why the two parted ways. He’s now working with Kristina "Kiki" Mladenovic, who is ranked No. 2 in doubles and No. 53 in singles.

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