Jelena Ostapenko has caused another major upset this season by defeating Jessica Pegula 6-4, 6-2, in the third round of the WTA China Open.

The Latvian ousted Eva Lys in three sets before Linda Noskova withdrew from their second-round match to set up the clash with the World No. 4. Meanwhile, the American received a performance bye in the first round after reaching the final of the Pan Pacific Open in Tokyo last week. She then defeated Anna Blinkova in three sets, putting the players in a similar situation ahead of their meeting.

Prior to this match, Pegula led their head-to-head 3-1, having most recently defeated the World No. 17 in Doha earlier this year. However, Ostapenko was able to narrow her opponent's lead with a win at the WTA 1000 tournament in Beijing.

Ostapenko played well with her usual power and aggressive style on display. She built up two break points in the opener, proceeding to successfully convert the first one by finding the outer edge of the court. She then went on to win the set 6-4.

In the second set, she asserted her dominance further by defeating the American 6-2, winning the match in 78 minutes.

This marked the 26-year-old's second victory against a Top 5 player this year. The first one came last month at the US Open when she shocked the tennis world by ousting top seed and defending champion Iga Swiatek in the fourth round.

Ostapenko will face the winner of the match between Liudmila Samsonova and Marta Kostyuk in the quarter-final at the National Tennis Center.