AUCKLAND, New Zealand (AP)Spanish qualifier Rebeka Masarova defeated second-seeded Sloane Stephens 6-3, 7-5 (5) at the ASB Tennis Classic on Wednesday as organizers of the WTA Tour event contended with a backlog of singles matches caused by persistent rain.

Matches had to be played indoors and without spectators to ensure the first round of singles was completed. On a day which was to be notable for the number of American players in action, Stephens struggled to adjust to the indoor setting and fell to the 130th-ranked Masarova in just under two hours.

The match was a holdover from the previous evening; Masarova led 2-1 on serve when play was suspended late Tuesday night. She immediately broke Stephens for 3-1 and, playing behind a strong serve, took the first set 6-3 in 41 minutes.

Masarova took an early 2-0 lead in the second set but Stephens broke in the fourth game to level at 2-2 and broke again in the sixth game for a 4-2 lead.

But Masarova broke back in the ninth game and came close to doing so again in the 11th game when she had three break points at 0-40 which Stephens was able to save. Masarova went up 6-2 in the tiebreaker and finally sealed the match on her fourth match point to claim her first win over a top-50 player since 2016.

”I thought I played some good points,” Stephens said. ”I thought I played well in some moments.

”Obviously, I wish I could have played better and done some things differently but overall I’m upset but not devastated. It’s the first tournament of year so I have to be realistic and just know there’s stuff to build on.”

Stephens hopes to play in Hobart, Australia next week to further prepare for the Australian Open which begins in Melbourne on Jan. 16.

Earlier, former Australian Open champion Sofia Kenin beat Wang Xinyu of China 7-6 (6), 6-3 and will now face top-seeded compatriot Coco Gauff in the second round.

”Unfortunately we had to go indoors but it was less windy so that’s a problem I didn’t need to worry about,” Kenin said. ”But the courts felt really fast, especially with who I played.

”She’s not an easy opponent and after the match I told my Dad I don’t know what’s better, to play indoors or outdoors against her because she’s a really tough player.”

Lauren Davis of the United States beat Tamara Zidansek of Slovenia 6-2, 6-1 and will next face seventh-seeded Danka Kovinic who beat Nao Hibino of Japan 6-1, 6-4.

Second-round matches involving Venus Williams, Leylah Fernandez and Emma Raducanu all have been postponed until Thursday when they may have to be played inside if rain persists.

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