When asked if she was still looking to top Steffi Graf's Open-era record of 22 Grand Slam singles triumphs, Williams told reporters: "It's something I'm obviously going to keep going for. It's definitely something in my mind, it's pretty important.
"I think everyone in general plays the match of their lives against me. I just have to always, every time I step on the court, be 100 times better. If I'm not, then I'm in trouble."
Saturday's defeat was Williams's earliest loss at Wimbledon since 2005.