Playing with solid redirection from the baseline and serving better as the match goes on, the world No.317 Kristina Kucova completed the third career win over a top 20 player as she beat a still-erratic Jelena Ostapenko 57 63 62 in Hong Kong.
The Latvian, making her tournament debut as Garbine Muguruza who will meet Sara Sorribes Tormo, won 12 of the last 13 points to take the first set 7-5. But the Slovak, who completed the second comeback win of the season after losing the opening set, claimed nine breaks from nine looks and sealed the win with a backhand return winner into the open court.
Kucova now awaits the Bulgarian lucky-loser Viktorija Tomova to reach her first WTA quarter-finals of the season. Tomova came out on top in a match filled with awesome shot-making, missed opportunities, and protracted baseline exchanges to beat world No.
79 Dalila Jakupovic, who won 10 of 14 close games in the match, 6-3 2-6 7-6, extending to 7-3 her win-loss record in final set tiebreaks. Ostapenko had also been the last opponent beaten by Alize Cornet before this week, in Cincinnati.
The Frenchwoman, who lost in the quarterfinals in both her previous appearances in Hong Kong to Venus Williams in 2015 and Jelena Jankovic in 2016, began her third campaign in the tournament with a routine 6-1 6-2 victory over Julia Glushko.
Cornet, who won her sixth career WTA title in Gstaad just one week after France had beaten Croatia in the World Cup final, finally ended a 5-match losing streak to even to 22-22 her win-loss record this season at WTA level.
Cornet continues her bid to reach at least the quarterfinals for just the fourth time in 25 tournaments in 2018, after she lost in the last 8 in Brisbane to eventual champion Sasnovich and Charleston, where she beat No.7 Garcia before surrendering to eventual champion Bertens.
She will meet for the first time Luksika Kumkhum who overcame Jennifer Brady 6-1 7-6(5) without losing her serve, after winning just the third tiebreak of the season. Dayana Yastremska emerged victorious from the battle between two big-hitting teenagers on Court 1, as she broke qualifier Fanny Stollar twice in each set to progress in straight sets, 6-4 6-4.