Serena Williams argues with US Open referee Brian Earley. Photo / AP
Boxing champion Claressa Shields has slammed tennis champion Serena Williams, revealing why it's not always a good idea to meet your idols.
The 23-year-old WBA and IBF female middleweight and super middleweight world champion said Williams used to be a idol, until they met at the 2016 Rio Olympics.
She told the Detroit Free Press she was upset after meeting her childhood idol.
"Well, one used to be Serena Williams," Shields, 23, said. "She used to be. I was able to meet Serena at the 2016 Olympics. She was just not nice.
"For me to look up to her like I did when I was a kid and then meet her in person and see how she's not fan-friendly, (that was upsetting)."
Shields won two gold medals at the Rio Olympics, the first US boxer to achieve the feat.
She has since turned professional and is undefeated with the two unified world championships.
"She was kind of mean to a lot of people at the Olympics and just kind of made me not want to be like her," Shields said. "Because I'm different. I'm a fan of her being a great athlete, just not a fan of her as a person, if that makes sense?"
Shields said her new role models are Floyd Mayweather and light heavyweight boxer Andre Ward.
It's been a hard month for Williams who has copped plenty of criticism over her outburst in the US Open final against Japan's Naomi Osaka.
Williams was cited for a coaching violation, destroying a racket and verbally abusing umpire Carlos Ramos in her defeat against Osaka and was fined Williams $17,000 for the incident.
She also accused the umpire of sexism for the violations.
It was hoped Australian audiences would get some answers when The Sunday Project 's Lisa Wilkinson interviewed the tennis star but Williams, and her publicist, kept a lid on the line of questioning.
Asked if she regretted smashing her racket, Serena's publicist interrupted: "That's four questions about the US Open so … change topic."
"I'm totally in your hands, Serena," Wilkinson insisted, asking her talent if she was comfortable answering more questions.
Williams, who initially attacked her treatment from the umpire as "sexism", simply claimed women should be able to do "half of what men can" and said she wished to put the saga behind her.
"If as a man you want to express yourself, without profanity, you should be able too. As a woman you should be able to do half of what a man can," she said.
"But I'm just trying to recover from that and move on."
Since the September 9 match, Williams has seen criticism from plenty of fields, including media, fellow tennis legends and even those from other sports.
Shields will fight undefeated Christina Hammer for all four middleweight world titles on November 17 in New Jersey, with the winner to be only the second-ever undisputed women's boxing champion.