BRISBANE, Australia -- No.8 seed Madison Keys continued a spectacular Wednesday for the United States at the Brisbane International, as her 7-5, 6-3 second-round victory over home favorite Samantha Stosur gave Americans an undefeated 3-0 record to complete singles play on the day.

"It's great to get two matches under your belt," Keys said in her post-match press conference. "It's always really important to feel good going into a Slam. You always just feel a little bit more comfortable once you can get that first win and then back it up with another one.

"Honestly, I think my serve has been really great and has gotten me out of some possibly tricky spots at times. And I think I've just been staying really calm and dealing with situations in a very calm manner and not freaking out."

Former US Open champion Stosur came into the match with a spotless 3-0 head-to-head lead in their rivalry, including a three-set victory at the Miami Open last year. However, Keys finally notched her first win over the Australian after 78 minutes of play, booking a place in the Brisbane quarterfinals for the first time in her career.

"I think it was just better execution," Keys said, regarding how she finally turned the tables on Stosur. "Sam obviously has a great serve and a great forehand and she's really tricky off of her slice. So I've known that in the past. I just felt like in the past I wasn't doing a great job at handling my side of the court."

The World No.13 followed the straight-set wins by her compatriots Alison Riske and Danielle Collins, to polish off an American clean sweep of Wednesday’s three singles matches. Keys, the second-highest-ranked American, hit 24 winners, including ten aces, to help propel her to her second win of the season, following a first-round victory over Marie Bouzkova on Tuesday.

"I think it was the first time today where I really went for it and just stood inside of the baseline, and knew I was probably going to mis-hit one or two," Keys stated. "But standing in and going for it and just trying to get a good rip off of the first ball was the best game plan."

It was Stosur who got off to a flying start in the tilt, as she blasted a return winner for an opening salvo en route to winning the first eight points of the encounter. The Australian built a 3-1 lead as her strong serving and powerful groundstrokes were in full flight

Keys, however, calmly held at love for 3-2, then quickly found her own targets on return to ease to triple break point in the subsequent game. Another blistering return winner gave the American the service break on her second chance, and the set returned to even footing at 3-3.

As the players moved to 5-5, Keys continued to zip through her service games. At that juncture, the American pasted a volley winner on the line to grasp two game points, then immediately slammed her fourth ace of the set to hold for 6-5.

In that game, Stosur ran into trouble serving to extend the set, as an ill-timed double fault at 30-30 handed Keys a set point. The eighth seed converted that chance, when a rally forehand forced a wide error from Stosur.

Everything started falling the American’s way as the second set commenced. With Stosur serving down 0-1, Keys won the first two points of that game after her groundstrokes clipped the netcord before falling in her favor. Keys finished off that game with a screaming winner down the line to break.

That, in fact, would turn out to be the decisive break of the match. Stosur used spectacular volleys to eke out service holds in hotly contested games as the clash wore on, but after missing a lone break point at 2-0, the former World No.4 was never able to get a true look in on the American’s service games in the latter stages of the set.

At 5-3, Keys leapt to double match point, and while Stosur thrilled the crowd with a return winner to save the first, the Australian shot a backhand return into the net on the second, ceding victory to the No.8 seed.

With the win, Keys sets up an all-American quarterfinal with World No.27 Collins later in the week. Collins triumphed in their only prior meeting, at the BNP Paribas Open in Indian Wells in 2018.

"[Collins is] playing incredibly well and really ripping and going for shots and she's making pretty much all of them right now," Keys stated. "So it's one of those things where I have to go out and just try to focus on my side and see what happens."

"[Collins is] hilarious and just very full of energy and a big personality, but she's also like the most caring, nice person that you'll ever meet," Keys added. "When she gets on a tennis court she just wants to destroy everyone who is in her way."

2020 Brisbane Highlights: Keys stops home favorite Stosur