MIAMI, FL, USA - Newly-minted BNP Paribas Open champion Naomi Osaka was handed the first test of her tenure as a tournament winner by the draw at the Miami Open, and the new World No.22 rose to the occasion.

Osaka recorded her eighth straight victory on Wednesday afternoon, as she ousted eight-time champion and childhood idol Serena Williams in the first round, 6-3, 6-2. 

"I was extremely nervous coming on the court. I don't know if anyone knows this but Serena is my favorite player," Osaka said on-court after the match. "Just playing against her is kind of like a dream for me, so I'm very grateful, and it's even better that I was able to win."

The Japanese No.1 handed the eight-time champion her first-ever loss before the fourth round in Miami, as Williams had reached that stage or better in 16 previous appearances. 

After the match, Osaka expanded on her admiration for the former World No.1: "She's the main reason why I started playing tennis, and just, I have seen her on TV so many times and I have always been cheering for her, so for me to play against her, and just sort of trying to detach myself a little bit from thinking that I'm playing against her and just try to think I'm playing against just a regular opponent was a little bit hard for me."

Though Osaka admitted to feeling the nerves before her first-ever match against the 23-time Grand Slam champion, the 20-year-old hardly looked it over the course of the one hour, 17 minute match.

Behind 18 winners, seven aces and four breaks of serve, Osaka powered her way to a second-round showdown with No.4 seed Elina Svitolina.

Though she lost the first five points of the match as Williams held at love to begin the match on what's ostensibly been her home court over the course of her career, Osaka settled in by winning a marathon first game on her serve in which she saved a break point.

From there, the World No.22 rode her big first serve in the clutch when she needed it, as she regularly found her spots on big points. 

From 3-2 down in the opener, Osaka claimed the last four games of the set, three of which went to deuce and two of those further which were on her serve. 

The second set began in similar fashion, as both players had to dig deep to maintain parity with each other. The most crucial game for Osaka came in the early going, as she saved the lone break point she faced in the second set in the third game, and edged her third break of the afternoon immediately after. 

Six of Osaka's seven aces for the match came in the second set as she slammed the door emphatically, and totaled 11 winners to just four unforced errors over the last eight games.

Williams, conversely, struggled to find her mark in swirling winds, as she hit 28 unforced errors to just 16 winners in the match overall.

"I was just trying to make my balls in and stuff. If you're playing against someone that's the greatest player, I'm not trying to look over on that side of the court too much, because I think I would freak myself out a little bit," she continued. "I would start thinking if she's struggling, if she's not struggling, if I should be doing this, if I should be doing that.

"I just tried to look on my side of the court and not think too much about what she was doing."

After dispatching the unseeded champion, Osaka will next face the No.4 seed in this tournament in Svitolina. The two have played four times, splitting the meetings, but the Ukrainian scored a win in their meeting this year in the semifinals in Dubai.

"I didn't look at the draw," Osaka said. "I just saw I was playing Serena, and I was, like, 'Oh, well. Might as well just focus on that.'"