SERENA WILLIAMS ADVANCES INTO DAY 7 OF THE MIAMI OPEN 2015.

Catherine Bellis, who had taken out No.29 seed Zarina Diyas en route to the third round, held serve once per set, but the No.1-seeded Williams was just too much overall, winning quietly in 41 minutes, 6-1, 6-1.

 The World No.1 lost just eight points in the 12 games she won, and just two points on serve. "It was tough. She's young, and her being an American and her just doing so well, you want to see people like her do well," Williams said. "So when you're up against them you have to kind of put that aside, even though I'm always cheering for her. 
But I have to put it aside and just play the match. "If you break down her age and ability and how well she handled the moment, it was good." Williams was asked whether she remembers playing the top players when she was 15. 
 "I don't remember. I have been playing a little over 10 decades," she joked. "But I just remember playing Steffi, and Monica was amazing to play. But I was never really playing at 15. I never played that well at 15 to play the professionals. 
I think I was still at school. I wasn't good enough back then. "I turned pro at 15, but I lost one and one to someone and didn't play for another two years." She was asked if she remembers who that loss was to. "Annie Miller. Sure did," she said. Bellis met the press shortly afterwards and was asked how she felt about the experience.