WIMBLEDON, England — Ash Barty played her first match as the No. 1 player in the world on No. 1 Court at Wimbledon, and she won.

The top-seeded Australian, who followed her victory at the French Open by winning a grass-court warm-up tournament in Birmingham, advanced to the second round at the All England Club on Tuesday by winning her 13th straight match. She beat Zheng Saisai 6-4, 6-2.

“It feels incredible,” Barty said about playing at Wimbledon as the top-ranked woman. “It’s a little bit of a bizarre feeling, to be honest. But I just try and go about my business the exact same way.

“This hallowed turf that we do get to play on is sacred, it’s beautiful. And you have to enjoy every minute.”

Defending champion Angelique Kerber also advanced, beating Tatjana Maria 6-4, 6-3 on Centre Court.

“I was really nervous, to be honest, because of course to (go) out there as the defending champion, it was really special,” Kerber said. “Walking on the Centre Court, playing there again, I mean, a lot of emotions, a lot of memories.”

Both Barty and Kerber are in the same quarter of the women’s draw, which means they could meet in the quarterfinals. Seven-time champion Serena Williams is also in that same quarter, and she also won, beating Giulia Gatto-Monticone of Italy 6-2, 7-5.

Garbine Muguruza, the 2017 Wimbledon champion didn’t make it through her first match. And neither did Maria Sharapova, the champion in 2004.

Muguruza, seeded 26th, lost to Brazilian qualifier Beatriz Haddad Maia 6-4, 6-4. Sharapova, who served for the match while leading 5-3 in the second, retired from her match with a left wrist injury while trailing Pauline Parmentier of France 4-6, 7-6 (4), 5-0.

The combative and combustible Nick Kyrgios advanced to the second round despite winning only five points in the fourth set. The unseeded Australian beat Jordan Thompson 7-6 (4), 3-6, 7-6 (10), 0-6, 6-1.