"I'm actually more excited," she said. "I know that I have the pressure on my shoulders because now nobody has anything to lose against me. The pressure is always on my side.
"But I am really looking forward to taking this challenge. It's a new situation for me. I will try to not think too much about this because I learned from the years before that I have to really focus on every single day here.
"It's a new tournament, new opponents. That will be my focus this week.
"Every player would like to beat me now. So I will just try to go out and not think about this. I'm going out to think like they are, to beat everybody on court as well, to win the matches.
"I think when I'm going in with this focus in the match, like I did also the last few months and tournaments before, that worked. So I will try to continue that."
Kerber's toppling of Williams in the rankings gives hope to other players, none more so than Karolina Pliskova, who the German beat in the final at Flushing Meadows.
Pliskova has had success against Kerber in the past but is not planning an assault on the top of the rankings just yet.
"For me it doesn't change anything if it's Serena or her at the top, there is still somebody else other than me," she said. "There's still some players in front of me, not only her, a few more.
"This is not my goal until a few years. I said I would like to win a grand slam next, then to become world number one.
"But obviously when it's a girl at number one, you know you beat her a few times, it's a big chance to get there, as well."
Venus Williams is the defending champion, but with a much stronger field in just the tournament's third year, the veteran knows it will be tough to retain her title.
"I'm just happy to be here, do the best I can, and hope to play just as well as last year," she said. " Everybody is playing well. There won't be an easy match. I mean, there never is an easy match."