NEW YORK -- Ajla Tomljanovic says her win against Serena Williams in the 23-time major champion's final match was the most conflicted she's ever felt. Tomljanovic played a steely match to defeat Williams 7-5, 6-7(4), 6-1 in the third round of the US Open.

"During the match I was so eager to win," Tomljanovic said. "I mean, I wanted to win as much as the next person because I didn't look at her like, 'Oh, Serena, her last tournament.' But then when it ended, it almost didn't feel right."

The win put Tomljanovic into the history books as the last player to defeat the American, handing Williams her 156th and final loss of her career.   

"I mean, no one's going to pronounce my name right," Tomljanovic joked. "That's going to suck.

"But I don't think I've of been part of tennis history, so that's pretty cool. I do feel a little bit like the villain."

Tomljanovic struck all the right notes in her on-court interview after the win, immediately ceding the stage to Williams. The key to scoring one of the biggest wins of her career was to stave off the doubts that have plagued her in the past. 

"I don't like to say it, but a little bit fearful of things going really badly out there because I'm playing Serena," Tomljanovic said. "I have faith in myself, but at the same time I have a little bit of doubt. I know that that's just coming from that bad side of Ajla that always has some doubt, like every normal person. 

"It was just about channeling the positive sides in me because I do have a lot of faith in myself and belief. I know I've put in the work over the last few months. Deep down I know I deserve to have that shot like I had tonight. It was just about channeling those emotions instead of the ones that are the bad Ajla."

More Serena reaction

As would be expected against the greatest competitor the sport has seen, Tomljanovic's win was never secure until the final point. Despite building a 5-1 lead in the final set, Tomljanovic watched as Williams saved five match points -- or in this case, career points -- in a protracted game that pushed the match past three hours. At 3 hours and 5 minutes, it would turn out to be the longest match Williams would ever play at the US Open. 

"I had this weird calmness," Tomljanovic said, "because I felt like if I get broken, I mean, so what? Serena broke me. Wow, I'm just like the next person she broke when she's down 5-1. I know she comes up with her best tennis when she's in the most trouble. I didn't feel like I'm choking it away or something. I thought I was getting outplayed on those match points.

"I just kept calm and actually took a page of her book. I know Serena one time said she only thinks about the next point. If I'm playing her, I might as well use her tactic."

Tomljanovic is now into the Round of 16 at the US Open for the first time in her career. The run has come in a season in which she made her second major quarterfinal at Wimbledon. She'll next face a red-hot Liudmila Samsonova, who has won 13 consecutive matches. 

"Just the fact that you don't have to have anything other than a supportive family, a dream, and just will and passion and love for the game to make it."

Tomljanovic said her mind was already on her next match. But when asked about Williams' impact on her career, Tomljanovic focused on the family element. She, too, was coached by her father, and her sister, Hana, played collegiate tennis at the University of Virginia. 

"From a young age I remember seeing them with their dad and thinking that's kind of like my story a little bit," Tomljanovic said. "Just the fact that you don't have to have anything other than a supportive family, a dream, and just will and passion and love for the game to make it. Not just make it, but what she's achieved is absolutely incredible. I don't know if it's ever going to be repeated while I'm still around.

"I still have years left in me. I want to dream bigger than I have so far because that's what she embodies."