Serena Williams still refused to entertain questions about a potential calendar Grand Slam but said she feels her bid to win Wimbledon "has finally begun" after beating her sister Venus in straight sets.
Top seed Serena moved into the quarterfinals with a ruthless 6-4, 6-3 victory over a resurgent Venus on Centre Court.
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All the talk at SW19 has been over whether the world No. 1 can win all four Grand Slams this year for the first time in her remarkable career.
Williams would not comment on the possibility of achieving that feat on Monday, but believes she is in great shape ahead of a last-eight encounter with Victoria Azarenka.
"I think I played solid. I knew that playing someone like Venus, that's beaten me the most, I have to be solid," Serena said. "I had to cut down on my unforced errors. I had to take a lot of chances. So I was able to do that.
"I feel like my tournament has finally begun. This is where I feel really comfortable in a Grand Slam."
Venus said it will take a special performance to deny her younger sister a sixth Wimbledon title, but the favorite is not getting ahead of herself.
"I'm just going out there and doing the best I can," Serena said. "I hope not to have a bad day. I have a couple, three rounds to play. (I'm) Just going to try to make it through the next one, the next one, then the next one.
"At the end of the day, I'll just do the best I can."