LONDON, Great Britain - Yulia Putintseva scored her biggest win at a major tournament of her career on Monday, shocking former World No.1 Naomi Osaka, 7-6(4), 6-2, to reach the second round at Wimbledon.

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"I'm not going to tell you my secrets," she jokingly opened her press conference when asked about her 3-0 head-to-head against Osaka.

"Honestly, I think I was able to keep my concentration up high all these three matches. I feel like whenever I am going down with Naomi in bad concentration, she's straight, like, doing so many winners. I was trying to make it as more uncomfortable for her as possible. That's the only thing."

The two-time French Open quarterfinalist had won her previous two matches against the No.2 seed - including one at the Nature Valley Classic in Birmingham two weeks agoFresh off her first WTA title at the Nürnberger Versicherungscup in May, she maintained her mastery over the reigning Australian and US Open champion after one hour and 35 minutes on Centre Court. 

Osaka had twice been to the third round at the All England Club - falling to eventual champion Angelique Kerber last year - and enjoyed a stronger start against her nemesis to start, edging ahead 3-1 in the first set.

Putintseva, who had never lost more than three games in any of her previous four sets against Osaka, soon leveled and forced a tie-break. 

"I was trying to concentrate on each and every point, especially when I was returning. It was a very tough match, especially mentally because she's always pressing, pressing, pressing. You have to stay cool. Sometimes when she does unbelievable winner, you have to accept it.

"To play on this amazing court, it's a great experience. I really loved it out there."

Again down 3-1 in the Sudden Death, the fiery Kazakh surged through six of the next seven points to capture the opening set as Osaka struggled with her range on key points.

Osaka looked to turn things around early in the second, saving two break points in the opening game as she held on a 2-1 lead.

A quarterfinalist in Birmingham, Putintseva flipped the script once more, racing through the final five games of the match to secure what is certainly her biggest win on the game's biggest stage, if not the biggest win of her career.

"I remember how much I hated grass courts. With my coach, I was fighting. I was saying that I don't want to play here. I used to play more on clay courts. Clay courts it's more spin, dropshots, serve kick and stuff. When I came on grass, was totally opposite. For my mental, it was like killing myself.

"It took some time."

In all, the unseeded 24-year-old played a clean match from start to finish, balancing 15 winners to just seven unforced errors as she converted three of seven break point opportunities in total. While Osaka managed 34 winners of her own, 37 unforced errors ultimately undid her aggressive gameplan and ended her fortnight at SW19.

Standing between Putintseva and a spot in the third round is flashy Swiss star Viktorija Golubic, who made it thorugh Polish teenager Iga Swiatek in straight sets earlier in the day.

"I just need to enjoy this moment that I beat a top player here, and to talk tactically about the next match with my team. I hope to put on some good stuff in this match and do good.

"I honestly don't care if it's a winner or if it's a ball which is forced error, as long as I am winning the point."