Thank goodness for the roof.

Although that won’t be what Angelique Kerber is thinking.

In its second year of existence, the roof over Arthur Ashe Stadium allowed for at least a few matches to be completed on Tuesday at the U.S. Open as rain pelted the other courts. A total of seven women’s first-rounders were completed–four inside Arthur Ashe and three elsewhere on the grounds in the early afternoon before the heavens opened.

Kerber wishes her match had never been played. The defending champion took the court under the closed roof and got blown away by Naomi Osaka 6-3, 6-1 in just one hour and five minutes. Kerber was on serve until 3-4 in the opening set only to see Osaka reel off nine of the last 10 games en route to her upset victory.

The Japanese 19-year-old blasted 22 winners to Kerber’s nine, all while committing fewer unforced errors (17 to 23).

“It was not my day; completely not my day today,” the world No. 6 lamented. “Of course it’s not the result (I wanted) and I’m sad…. I think she’s a very aggressive player, but I [knew] this before. She served very well and was going for it. Yeah, she played a very good match from the beginning.”

Naomi Osaka of Japan reacts as she plays Angelique Kerber of Germany on the second day of the US Open Tennis Championships at the USTA National Tennis Center in Flushing Meadows, New York, USA, 29 August 2017. The US Open runs through September 10. EPA-EFE/JUSTIN LANE

“I was really happy because I grew up watching the greatest players play on that court,” Osaka said. “So to win a match on it felt really special.”

A potentially great player in the future–if not the present–took the court at the beginning of the night session and Madison Keys treated the American fans to a 6-3, 7-6(6) victory over Elise Mertens. Keys failed to serve out the match at 6-5 in the second and eventually saved a set point at 5-6 in the tiebreaker with a blistering forehand. She sealed the deal two points later.

“She was a tough player,” Keys said of Mertens. “She’s obviously playing good tennis. I’m just happy to get the win.”

As for the roof, although it is a God-send whenever it rains in New York, it also makes for a lot of noise. Noise, noise, noise, noise! The U.S. Open is known for loud, boisterous crowd and the roof only makes the crowd sound even louder. Rafael Nadal complained that he could not even hear the ball during his win over Dusan Lajovic on Tuesday afternoon. Keys also said it was loud, but she didn’t mind.

“It was definitely loud in here, but kind of had home-court advantage. I had all these wonderful people cheering for me tonight.”

Also advancing to round two on the women’s side were Karolina Pliskova, Jelena Ostapenko, Barbora Strycova, Yanina Wickmayer, and Sorana Cirstea.