DUBAI, UAE - For the third match in a row at the Dubai Duty Free Tennis Championships, qualifier Jennifer Brady faced an accomplished Top 20 player on the other side of the net - and for the third time the underdog pulled off the upset, adding No.9 seed Garbiñe Muguruza to the scalps of No.3 seed Elina Svitolina and Marketa Vondrousova with a pulsating 6-7(5), 6-3, 6-4 triumph to reach her third career WTA Tour semifinal, and first at Premier level.

The American, who previously reached the last four at Hong Kong 2017 and Nottingham 2019, prevented Australian Open runner-up Muguruza from posting consecutive semifinals for the first time since Doha and Dubai in February 2018 in their first encounter. Recovering brilliantly from the loss of a first set in which she had held a 5-2 lead, Brady held firm during spells of brutal hitting from the former World No.1, keeping her own serve and forehand firing at crucial times as she sent down six aces, struck 22 winners and saved nine out of 10 break points against her.

Nonetheless, Brady wasn't wholly satisfied with her game. "I wasn't feeling my best," she told reporters. "Maybe didn't play my best tennis, but just found a way to stay in there, compete, come out on top."

The 24-year-old said that she had taken a key lesson from two of her recent matches, a 6-7(4), 7-6(2), 6-3 defeat of compatriot Amanda Anisimova in the first round of Beijing last year - which coach Michael Geserer referenced on court in the third set today - and her 7-6(5), 6-1 loss to Simona Halep at the same stage of the Australian Open last month.

"It was the first week [in Beijing] we worked together. We didn't know each other. Obviously, it was the first time playing Amanda. I mean, she's a great player, up-and-comer, but it was a grind. It was a tough match. I think I was down a break. Sort of the same scenario [to today]," Brady said, referencing her coaching visit.

"He was just trying to get my mind on just competing, just playing every point, fighting until the end."

Brady emerged on top of the opening stages of the match in which both players felt out each other's games in their first meeting, and was particularly impressive in coming up with her best serves to get out of danger as she staved off two break points in the first game and two more in the third en route. As though ruing her missed opportunities, Muguruza's backhand let her down in the next game, finding the net twice to hand Brady a 4-2 lead. One emphatic hold later, and Brady found herself in prime position to pull off her third Top 20 upset of the week.

However, Muguruza's ability to find another level has been a hallmark of the former World No.1's best results, and she would find some truly special form to steal the set from Brady. A ferocious off forehand winner carved out a break point as Brady served for the set - and with Muguruza piling pressure on the World No.52 with relentless depth and aggressive returns, Brady ultimately found the net with consecutive forehands to drop serve.

Though Brady battled valiantly to resist, the savagery of Muguruza's hitting would reach unplayable levels at times as her comeback gathered momentum with 14 winners and a 78% first serve percentage. Brady would be hindered, from 3-1 up in the tiebreak, by a double fault and a dead net cord to open the door for the two-time major champion - but Muguruza was irresistible thereafter, particularly in outhitting Brady with phenomenal line-to-line power at 5-5 to bring up her first set point, taken after a deep return elicited a Brady backhand long.

The World No.16's intensity carried over into the first half of the second set, with determined moves into the forecourt now augmenting her baseline - but Brady, displaying the same fortitude with which she had overturned a 4-6, 1-4 deficit against Vondrousova yesterday, would battle hard to keep apace with her opponent. The Nottingham semifinalist would get her reward midway through the set when Muguruza, having fired a bullet of a backhand winner, held break point to take a 4-2 lead.

Brady held firm, saving that point with a punishing forehand crosscourt winner of her own and holding with a backhand winner down the line - and suddenly, momentum swung firmly back her way as Muguruza's game deserted her. The Shenzhen semifinalist collapsed after that missed opportunity, conceding her serve once with two cheap forehand errors and two double faults to go down 3-4 - and then again with another double fault and a similar spate of mistakes from the backhand for the set.

For Brady, the midpoint of the set had effectively been the beginning of the match. "I think really the match started from 3-2 in the second set for me," she said. "Never really felt like I was in the match from the very beginning."

The deciding set would be a tightly contested affair with almost nothing between the two competitors, who would each post impressive service holds whenever they stepped up to the line through the first nine games. Indeed, it was Muguruza - who would finish with more winners than Brady, 30 to 22, and the same amount of unforced errors, 22 apiece - who carved out more opportunities for herself during this passage of play, holding triple break point in the third game and a tantalizing 0-30 lead at 4-4.

Yet it was the Brisbane quarterfinalist who was now raising her level when it mattered: a scorching backhand crosscourt winner fended off one of the early break points, and she would get out of the 4-4 game by slamming down an ace followed by a service winner. And as had been the case in the second set, escaping those games would have a carry-over effect. Serving to stay in the match, a couple of loose forehands put Muguruza down match point - and although she saved the first, Brady hammered an off forehand winner to bring up a second, before emerging on top of yet another high-octane rally as Muguruza sent a backhand long.

Standing between Brady and a maiden final will now be either No.1 seed Simona Halep or No.7 seed Aryna Sabalenka.

"Obviously, I played Halep in Australia. Never played Sabalenka. I mean, they're obviously great players, competitors. I'll probably sit, relax, watch the match. Yeah, whoever I play, it will be a tough one," Brady said. 

"[Against Halep at the Australian Open], I had set points in the first set. I wasn't able to close it out. A couple good points from her, but maybe a couple passive shots from me. It's more just every point, just playing the same. Regardless [if it's] match point, first point, set point, just treating every point the same, leaving it all out there."

2020 Dubai Shot of the Day: Jabeur’s running forehand