INDIAN WELLS—World No. 1 Simona Halep says Serena Williams should have been seeded first in her comeback tournament at Indian Wells.

The top-seeded Halep, who defeated Qiang Wang, 7-5, 6-1, to advance to the BNP Paribas Open quarterfinals, said Williams should have been seeded first on a protected seeding because she was world No. 1 when she took a break from tennis to give birth to her daughter.

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"I think she should have been actually No. 1 seed in this tournament because she left as No. 1 in the world," said Halep, who raised her record to 17-1 on the season. "And to give birth, it's the best thing in the world. It's more than a sport. So I think she should have been ranked as she left.

"Not taking the ranking because she didn't play tournaments, but just protected ranking for—I don't know how many tournaments you have, like, eight. She could be the No. 1 seed for that, for those tournaments. This is my opinion."

Halep, who played the first match on stadium 1 court this morning, was in the stands for about a set of the Venus Williams vs. Serena Williams showdown on Monday night. 

"I'm the world No. 1 in this moment, but I just watched the best player in the world," Halep said. "So, no, I'm not thinking about anything. I just do what I feel. I felt to come because I admire a lot the sisters."

Asked what she can learn from watching the Williams sisters, Halep replied "everything."

"Also the motivation, the game, the way that they are hitting in important moments, the way they stay there and they are focused for every ball," Halep said. "So everything in general I have things to learn."

Photo credit: Miami Open