Serena Williams has responded to young tennis player Sloane Stephens, who slammed her, calling her a sore loser and bad mentor.

The 20-year-old made scathing comments in the upcoming issue of ESPN magazine.

“She’s not said one word to me, not spoken to me, not said hi, not looked my way, not been in the same room with me since I played her in Australia,” Stephens revealed.

“And that should tell everyone something, how she went from saying all these nice things about me to unfollowing me on Twitter," Stephens continued.

Williams, 31, responded on Tuesday while in Spain during the second round of the Madrid Open. She defeated Lourdes Dominguez Lino 6-2, 7-5, and one of the reporters asked about Stephens’ interview.

“I don’t really know. I don’t have many thoughts. I’m a big Sloane Stephens fan and always have been. I’ve always said that I think she can be the best in the world. I’ll always continue to think that and always be rooting for her.

So I really just always wish her — and anyone, really, especially from America — the best. We don’t have that many American players, so it’s always exciting to see so many young players doing so well," she continued.

Stephens also said in the interview that Williams was not a good mentor, barely speaking or giving advice to the newcomer, who began tennis at an early age, as did Williams.

“For the first 16 years of my life, she said one word to me and was never involved in my tennis whatsoever. I really don’t think it’s that big of a deal that she’s not involved now. If you mentor someone, that means you speak to them, that means you help them, that means you know about their life, that means you care about them. Are any of those things true at this moment?" 

After Williams’ comments at the Madrid Open, Stephens seems to have had a change of heart. She tweeted “Guilty of being naive. Much respect 4 @serenawilliams, a champ & the GOAT. We spoke, we’re good. ONWARD! #lifelessons.”