BEIJING, China -- Qualifier Jennifer Brady staged a stirring comeback against her fellow American Madison Keys on Wednesday, fighting back from a deficit of a set and a break to upset the No.11 seed 2-6, 6-4, 6-4 in the second round of the China Open.

In the first professional meeting between the two powerful players, World No.66 Brady turned the match around after falling behind a set and 3-1, eventually steering past her compatriot after one hour and 56 minutes of play, and earning her fourth Top 20 win of the season in the process.

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“[Keys is] obviously a very tough opponent," Brady said, after her win. "She’s very strong, very powerful, hits huge strokes. If you give her any time or a short ball, the point’s over. That’s really difficult, puts a lot of pressure on you especially on your own service games, trying to hold. She also has a big serve and she’s really able to dictate off her serve and first shot."

"The first set and a half, I would say I wasn’t playing my game," Brady continued. "I was just letting her dictate and take control and be the one in charge. I feel like I got a bit lucky with a few points here and there and was able to turn around the match. Towards the end of the third I was able to play better and more offensive and serve a lot better."

2016 China Open semifinalist Keys hit 42 winners during their encounter, well outpacing Brady's 15, but the seeded player's winner total was negated by 48 unforced errors throughout. Brady was stronger on second serve in the final set, winning 69 percent of those points, while Keys could only win 42 percent of her second-service points in the decider.

"I think it was just mentally, being able to stay in there and fight," said Brady. "Not give in, not look at the score, just stay positive and stay within myself. Look to play my game and be more aggressive, knowing that if I stay in there, things can happen. And they did. I was happy they did.”

Keys was under duress in two of her first three service games of the match, but was able to fend off three break points combined during that stretch to reach 3-2. That steeliness paid dividends when she attained the first break of the tilt in the very next game, using powerful groundstrokes to tee up a backhand winner on break point, and take a 4-2 lead.

The No.11 seed continued to ease past Brady as the set continued, using stellar serving to hold for 5-2, then cracking a handful of blistering return winners on her way to a set point in the following game. Keys converted that chance with another return winner off the forehand side, giving her a fourth straight game and the one-set lead.

Brady quickly fell behind in the second set as well, hitting three consecutive double faults from game point up to drop serve and hand a 2-0 lead to Keys. However, Brady finally converted a break point in the next game, firing an error-forcing forehand to pull back on serve.

Keys cracked a forehand winner down the line on break point of the next game to pull ahead 3-1, but miscues off of that wing in the subsequent game ceded another break to Brady. At this juncture, Brady started to survive the rocketing returns from Keys more often, and the qualifier held through to 4-4, as the momentum of the match began to shift.

Brady then saw a break point in the next game after a double fault by her opponent, and Keys followed up by blasting a forehand long to give Brady a pivotal lead at 5-4. Energized by her newfound advantage, Brady zoomed through a service hold at love, including two service winners, to clinch the second set after twice being a break behind.

Now into a final set, Brady had to withstand a break point in her first service game, but pulled out a hold. The qualifier hung with her seeded countrywoman throughout: Keys held with an ace for 2-1, but Brady countered by holding for 2-2 with a service winner; Keys raced through her next service game, but Brady deployed deft dropshots en route to her own love hold for 3-3.

Finally, it was Brady who grasped the decisive break, converting her third opportunity in the following game after a long error by Keys and leading 4-3 with serve. Brady would go on to serve for the match at 5-4, and garnered a match point with a superb forehand passing winner. One final long forehand by Keys gave Brady the comeback victory and a spot in the third round.

Next up for Brady will be the winner of the last remaining second-round match, between 5th-seeded US Open champion Bianca Andreescu of Canada and Elise Mertens of Belgium.