Agnieszka Radwanska says she will have to play "100%" to beat Angelique Kerber in their Wimbledon semi-final this afternoon.
The No.3 seed, the first Pole to reach a grand slam semi-final, will become the world No.1 if she wins the title.
The 23-year-old battled past Maria Kirilenko in the last eight in a tough three-setter, and as the higher-ranked player - Kerber is seeded eighth - she admits she has a great chance to reach the most prestigious final in the game.
"It's always an opportunity. It doesn't matter who you play," Radwanska said.
"This is the semi-final, so it means that we have both already played a couple of good matches, also against seeded players.
"It means she's also playing great tennis this tournament. Really I have to play at 100% to win that match."
Dipping below her usual standard cost Radwanska at last year's US Open, where Kerber claimed her scalp in the second round.
And Kerber went on to reach the semi-finals, so unlike her opponent she possesses experience at this stage of a grand slam.
"It's one of the best things in my career right now to be in a second semi at the grand slams," Kerber said.
"I will go out there and try my best. I have nothing to lose right now. I will just try to play good tennis and enjoy it. I know I need to play at my highest level to beat her."