Katerina Siniakova scored the sixth Top 10 victory of her career with a 7-6(4), 6-2 upset of No.1 seed Serena Williams at the Emilia-Romagna Open.
The Czech World No.68 needed one hour and 37 minutes to record her first win over a player in that echelon since defeating Naomi Osaka at Roland Garros 2019.
Siniakova saved a set point serving down 4-5 in the opening set with a forehand winner and pulled away in the second to win 16 of the last 18 points. The result moves the two-time WTA titlist into her second quarterfinal of 2021 following Istanbul last month and improved her season record in main draws to 5-6.
The lesson for Siniakova, whose singles form this year had hitherto been some way off the level that saw her win Shenzhen and Bastad in 2017, was to take her mental approach into more matches.
"Not every day is really amazing", she said. "If you go to play against a player like this, you really have nothing to lose, so I came up and wanted to enjoy it.
"In the beginning I was so nervous, but when it was 1-1 everything just came down and I was just really enjoying it - I was feeling so free and so easy that it just really went my way. So I should really try harder to feel like this in every match, because you should enjoy what you're doing - and that's what I'm trying to find. I can play like this. I can do it not just in one match, and I hope it will not be just this match."
The same applies to Siniakova's growing tally of upsets, which also include defeats of Simona Halep (at Shenzhen 2017) and Caroline Wozniacki (at Bastad 2017).
"I should be more proud of them," she said. "My statistics against top players are really good, and a lot of players would want this. I should be really proud and believe more in myself - this match can open my eyes and I will try to keep it like this."
Both players started well, each saving a break point in their opening service games and going to-to-toe from the baseline in high-octane exchanges. There would be no further opportunities for either to break until Williams carved out a set point in the ninth game.
But after Siniakova had saved it, Williams fell away, with her double faults mounting alarmingly under pressure.
One came down break point to concede the first break of the match at 5-5 - and though Siniakova contributed a similarly wobbly game in attempting to serve out the set, Williams could not take advantage. The American coughed up another pair of double faults in the ensuing tiebreak, as well as a host of errors as she went for too much, too soon.
"I didn't do a lot of mistakes, and I think she felt it," Siniakova said. "I think she was trying to go harder and doing a lot of mistakes, which helped me - I'm really happy I could keep my level all match."
A pair of crunching winners to capture the Siniakova serve at the beginning of the second set proved not to be the start of a comeback, but a last hurrah. Williams was growing increasingly frustrated by Siniakova's ability to turn stellar defence into line-hitting offence, and was broken back immediately.
By now, everything was falling into place for Siniakova as she conjured winners from every position on court, with even a mishit smash setting herself up for the simple pass. As Williams's tally of double faults rose to seven, Siniakova won 15 straight points to leap from 2-2 to 5-2, and closed out victory on her third match point as Williams sent a forehand long.
The 23-time Grand Slam champion Williams had paid tribute to the greatness of the ATP's 20-time Grand Slam champion Roger Federer after her first-round win, calling him "a synopsis of greatness and class". The legendary pair of former World No.1s were in sync Tuesday as Federer's return to action in Geneva also ended in second-round defeat, 6-4, 4-6, 6-4 to Pablo Andujar.
Martic, Gauff move into second round
Earlier in remaining first-round matches, No.2 seed Petra Martic and No.3 seed Coco Gauff both got their Parma campaigns off to winning, but contrasting starts.
Alongside new coach, former Roland Garros champion Francesca Schiavone, Martic ended a dry spell last week to reach her first WTA 1000 semifinal in Rome. The Croat continued her resurgence with a fine display against Varvara Gracheva, defeating the Russian 6-4, 6-2 in one hour and 21 minutes for the third time in the past year.
No.3 seed Gauff is also off a maiden WTA 1000 semifinal run in Rome, and edged Kaia Kanepi 7-6(6), 7-6(7) in a pair of tiebreaks. The scoreline does not reflect the wild fluctuations of momentum over the course of the match.
Gauff, 17, came from 3-5 down in the first set, and saved one set point in the tiebreak. But from 5-1 up in the second set, she lost five games in a row, and ultimately needed to save two more set points in another tiebreak before crossing the line on her first match point.
World No.66 Kanepi's accuracy with her heavy groundstrokes oscillated wildly over the course of the match and was largely responsible for the scoreboard rollercoaster. Gauff once again impressed with her resilience to find her best tennis when she needed it, despite having seemingly lost control of the run of play.
Stephens upsets Kasatkina in second round
Sloane Stephens battled into her second quarterfinal of 2021 with a 1-6, 6-4, 7-5 upset of No.4 seed Daria Kasatkina in 2 hours and 5 minutes.
The American now leads the head-to-head between the two former Top 10 players 3-1 after an arduous match decided mostly by competitive instincts. In 29 games, Kasatkina held serve only six times - four of which were in the first set - and Stephens only five times.
Kasatkina dominated the opener, coming up with some delightful touches of finesse. But as conditions grew gustier, her shotmaking efficiency decreased markedly. So too did her authority behind her serve: across the match, the Russian won only 50% of the points behind her first serve and 22% behind her second.
Stephens also suffered behind her delivery, winning 27% of her first serve points and none of her second serve points in the second set.
But the American was able and willing to hit through the wind more as the contest drew to a close, and the grittier competitor at its dénouement. The pair engaged in a series of gruelling rallies in the third set, and more often than not it was Stephens whose defence proved impenetrable or who could find a winning shot.
Kasatkina found three spectacular winners to stave off the first three match points she faced, but it was too little, too late.