PARIS, France – No.14 seed Madison Keys produced her best tennis of Roland Garros 2019 to win through to the quarterfinals with a 6-2, 6-4 success over Katerina Siniakova in 78 minutes.

Keys, a model of consistency in majors, has now reached the last eight in four of the last six Grand Slam events, and simply had too much for an opponent who had reached the second week at such a standard for the first time in her career.

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“It’s always a special and stressful experience every single time,” she said when questioned if going deep in majors is starting to feel routine. “I'm happy that I've gotten through to fourth rounds and quarterfinals now a couple times now. But it never, never feels routine.”

Balance was critical to Keys success. Her winner count of 26 match the number of unforced errors she made and was representative of the manner in which she admirably juggled her attacking instincts with the pragmatism required to success on clay.

“I think in the past I have tried to go either stay as aggressive as I would on any other surface or go the complete other direction and get a little bit more passive and try to rally a bit more,” he said. “So it's more just finding a middle ground than understanding that more balls are going to come back and not to panic or press more. That's been the biggest thing.”

Siniakova, who had stunned WTA World No.1 Naomi Osaka to reach this stage, was unable to reprise such a performance, despite coming into this meeting on an eight-match winning streak against American opponents.

Having survived a near-two-hour five setter against qualifier Anna Blinkova in the third round, Keys enjoyed an altogether more comfortable passage in the Parisian drizzle.

 “I was happy to close it out in two sets. Playing three sets in such heavily conditions isn’t much fun,” she admitted in her on-court interview.

Although the first two points went the way of her opponent, 10 in succession followed for the 24-year-old, whose hitting power forced errors with regularity, particularly in the early stages of the contest.

Playing a reactive role, Siniakova was doing her best to get Keys to miss, and while there was a dip in the performance of the Charleston champion in the middle part of the set, she was rewarded for her aggression with two further breaks.

After 32 minutes, the opening set was sealed, Siniakova caught in limbo between the baseline and the net as the WTA World No.14 sent a crushing forehand down the line past her, a fitting motif to what had passed. 

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The second proved to be altogether more competitive, with Siniakova finding an edge to her game that was previously missing. The efficiency of the 23-year-old’s strokes improved, and their greater weight and accuracy meant that her both her drops and her net play became more effective.

Having been dominant in the opening set, Keys stood firm in the face of this renewed challenge and the first nine games all went with serve. With Siniakova serving to stay in the match, the American found her very best tennis, crushing a succession of returns to set up a couple of match points, the first of which was taken as the Czech fired wide.

Ashleigh Barty awaits in the last eight, and Keys is naturally respectful of the No.8 seed.

“It's going to be a tough one,” she said. “I think she's obviously playing well to make quarterfinals, and I didn't get to see how she played today, but I feel like clay actually suits her game really well with her kick serve and slice and all that. 

“I'm going to have to have a game plan set to be ready for her.”

Keys won the only previous meeting between the two players on clay, two years ago at Roland Garros.