BIRMINGHAM, Great Britain - Yulia Putintseva earned her second Top 5 win of 2019, and the biggest win of her career at the Nature Valley Classic, top seed Naomi Osaka, 6-2, 6-3.
"I was expecting a tough battle, which is what happened, and the score doesn't tell the fight that was there," she said in her post-match press conference. "So many games went deuce, advantage, and I could have lost those, but in the end I won them. I'm happy to get through and another win on grass."
The Kazakh beat Osaka in their only previous meeting last year at the Hobart International - before the Japanese star went on to win the US Open and Australian Open titles - and maintained her mastery over the World No.1, sealing the upset after 68 minutes on Ann Jones Centre Court.
"I got a lot of tough draws in Birmingham in the past. I've lost to [Barbora] Strycova and another to [Michelle] Larcher de Brito, who is very good on grass. This year, I started to feel better with my movement on grass, but I'm happy to have some matches before Wimbledon. I hope I can do even better here."
Though Osaka's 16-match Grand Slam winning streak came to an end at Roland Garros, she kicked off her grass court campaign with a topsy-turvy opening round encounter with Maria Sakkari on Tuesday. Still, she suffered a slow start against Putintseva, losing the first five games and ending the first set with 23 unforced errors.
"It feels great to beat a World No.1, and it's always great to beat a player as good as Naomi. The last time we played was a different match because it was very windy, and on a hardcourt."
The fiery Kazakh began the year with a win over Sloane Stephens in Sydney, and reached her best-ever Premier Mandatory result at the Miami Open, where she reached the fourth round - all leading up to her first career title in Nürnberg.
"The title gave me a little more confidence in my game, but I can't say I've played so much better since, because I was already playing well in Nürnberg and in the weeks before. My game was getting there, but it was just a matter of how many matches I've been playing. I had more than I usually get, and that helped my level."
Against reigning World No.1s, she had thrice lost to Serena Williams in her previous encounters with the WTA's top ranked player - pushing the 23-time Grand Slam champion to within five points of defeat at the 2016 French Open.
"It's a good feeling when no one expects you to win, because you can play with more freedom. In the end, it doesn't matter because you're not focused on who is the favorite. You're just there, trying to do your best."
She nonetheless kept her composure on Thursday, even as Osaka began to work her way into the match, shaking off a late break of serve to break straight back and put herself a set away from victory.
Osaka seemed to steady in the second set as she won three straight games to find herself in front for the first time in the match. Putintseva quickly reversed the trend and won the final four games of the match, serving out the win on her first opportunity.
In all, it was a clean match from the Kazakh, who struck 11 winners to just nine unforced errors and converted six of 10 break point opportunities. Osaka ultimately ended the match with more winners but also with more errors, 21 to 37, respectively.
"These are my first matches on grass, but they're all so important because the season is so short, just a few tournaments. I felt like I needed to be more free with my shots, and not worry about what happens. I was more aggressive and changed the rhythm; that helped me win the match."
Up next for Putintseva is 2018 Wimbledon semifinalist and No.8 seed Julia Goerges, who defeated Russia's Evgeniya Rodina in straight sets.