Serena Williams’ loss to Naomi Osaka in the finals of the U.S. continues to garner controversy, days after the tournament’s end.

The incident, which echoed incidents involving Williams at both the 2009 and the 2011 U.S. Opens, saw the star lash out against officials for what she thought was unfair treatment on the court.

The dominant Osaka won the match after Williams drew a third violation for insulting chair umpire Carlos Ramos during a lengthy argument that included her calling him a “thief.”

Williams argued against the ruling, saying that Ramos’ decision, which awarded a game to her opponent, was sexist.

"To lose a game for saying that is not fair," Williams said. "There's a lot of men out here that have said a lot of things and because they are men, that doesn't happen."

She wasn’t the only one with that opinion, with several tennis pros taking to Twitter to speak out against the ruling.

“If it was men’s match, this wouldn’t happen like this,” Victoria Azarenka wrote. “It just wouldn’t.”

Tennis legend Billie Jean King said that the call was a sign of a greater double standard that exists in tennis.

“When a woman is emotional, she’s “hysterical” and she’s penalized for it. When a man does the same, he’s “outspoken” & and there are no repercussions.” King wrote.

She thanked Williams for calling out the double standard, and said more women need to speak out before changes will be made.

Other pros took issue with the call itself, saying that Ramos overstepped his bounds in giving Williams the three warnings that cost her the match.

“Worst refereeing I’ve ever seen,” wrote retired Grand Slam champion and long-time friend of Williams, Andy Roddick.

Thirty minutes later, he clarified, saying that the tweet had been an “emotional first take.”

“He’s within his power to make that call,” Roddick wrote. “I’ve seen an umpire borderline coach a player up, and another dock a game for being called a thief in same tourney. There needs to be some continuity in the future.”

“This is crazy!” Renna Subbs wrote. “The coaching violation was questionable.”

“I see a ton of coaching from the box and that was marginal. The racket break was legit penalty,” she continued, “then to give another warning for calling the umpire a thief. Come on!”

In a now deleted tweet, Jessie Pegula said that the game had the “worst refereeing” she’d ever seen.

“Coaching warning was nothing, then the game penalty,” Pegula wrote. “What a joke.”

Notable tennis coach Michael Joyce disagreed with Pegula, his former student, saying that Williams “wasn’t a victim” in his opinion.

“Well there’s never consistency,” Joyce wrote. “The coaching violation wasn’t a big deal and she made it personal. Smashing the racket automatic. At that point she should of tapered down.”

“Coaching is called often. Especially when it’s that blatant,” Joyce wrote. “The racket smash is automatic. And whenever you call the ref something personal like a thief, there’s a pretty good chance for a code.”

He also poked fun at Williams’ claim to Ramos that she was not a cheater because she had a daughter.

“The coaching violation can come at anytime and most players just move on and not talk about having a baby,” he wrote.

Voices like Joyce seem few and far on Twitter, with few players standing up for the calls made Ramos.

Tennis writer Ben Rothenberg was quick to defend the decision, saying that Ramos’ rulings were “all fair”

“Mouratoglou admitted to ESPN that he coached. Thus, the warning was correct by Ramos,"Rothenberg wrote. “Then, racket abuse warning was indisputable. Williams felt entitled to having coaching warning retracted, which never happens.”

“So she ranted abusively, and got a third warning.”

The Times tennis correspondent Stuart Fraser agreed with Rothernberg, saying in a response that the umpire was being “let down” by his colleagues.

“Carlos Ramos one of the few umpires not afraid to call a rules violation against the top players when it is due,” he wrote.

“It is his colleagues who are letting him down with their inaction, which then leads to situations like this in which players feel they are receiving unfair treatment.”

No matter what side of the argument they fell on, players were quick to give their support to Osaka, who’s first career slam win was overshadowed by the controversy.

The 20-year-old, who made it to the tournament’s finals only dropping one set, was tearful during the award ceremony, hiding her face and apologizing for her victory as fans in the crowd booed and jeered.

“Despite all the drama surrounding the match, @Naomi_Osaka_ is a Grand Slam Champion and deserved the win!” Christopher Eubanks wrote.

“I hope all of this doesn’t overshadow a remarkable two weeks for her and her team!”

“Congrats @Naomi_Osaka_ on the first of many!” Denis Shapovalov said in a tweet, “Well deserved.”