Serena Williams answered to the reporter's question and it went viral.

Serena Williams beat Anett Kontaveit in straight sets to reach the quarter-finals, where she will face Qiang Wang.

The reporter’s question came after Williams had struggled in her third-round match against Caty McNally, which she won in three sets.

Serena Williams was asked a difficult question during a post-match press conference at the US Open, and she gave an equally difficult answer. Williams didn’t take the bait, instead choosing to answer the question with a question of her own.

“I’m sorry, I’m not sure what you’re referring to,” Williams said. “I think I need to apologize for? I’m sorry, I’m not sure. When asked if she felt like she was “back to her best level”, Williams gave a brilliant answer.”

“I don’t know what that means,” she said. “I just try to go out there and compete as hard as I can. Every day is different. I feel like I have been playing really well. Obviously I had a tough match today. But I feel like if I just keep going, the results will come.”

And when asked by a reporter how she was feeling after the match, Williams delivered a brilliant answer. “I’m feeling really good,” said Williams. “I’ve been working hard and I’m just happy to be out here competing and doing what I love.”

The US Open is the only grand slam that Williams has yet to win, and she will be hoping to go one better this year. Williams is next in action on Saturday when she takes on unseeded Sloane Stephens.

Serena Williams has been in great form at the US Open so far and she will be hoping to continue her good run when she takes on Qiang Wang in the quarter-finals.