21st-seeded Madison Keys has never beaten former world number two Agnieszka Radwanska before. The Pole leads in their head to head, 3-0, which includes a three set victory at Wimbledon in 2013. Keys is playing in her first Wimbledon quarterfinal, and looks to avenge that loss from two years ago.

Grass is both players’ best surface, despite the contrast in their playing styles. Keys is an aggressive baseliner with a massive serve, which the grass court will always favor. Her incredibly powerful, flat strokes penetrate through the grass and trouble her opponents.

Radwanska is a crafty counter puncher, who troubles her opponents not with power, but with her consistency and phenomenal defensive skills. At her very best, she is virtually a backboard. The grass favors her game due to her ability to slice, make drop shots and play the net. She is also able to win a lot of free points from her quick first serve, and hits many more groundstroke winners than she does on other surfaces. Her shots do not bounce very high, which makes it tough for opponents to return her balls on the grass.

This contrast in styles has always favored the Pole, with her most recent victory over Keys at the China Open in 2013. However, Keys’s game has evolved since then, evidenced by her magical run at the Australian Open earlier this year. She defeated two-time Grand Slam champion Petra Kvitova along the way to the semifinals, falling to Serena Williams.

Radwanska has had a frustrating 2015, her ranking dropping outside the top 10 for the first time since 2011. Her game has not been as effective as before, and her opponents have found ways to hit through her. At Roland Garros this year, she fell in the first round to unseeded Annika Beck.

The Pole has found her form at Wimbledon this year, her favorite Grand Slam tournament. She has yet to drop a set, and produced a solid win over former world number one Jelena Jankovic in the fourth round, who upset defending champion Kvitova. If she were to get past Keys, she will make her third semifinal appearance in four years at the All England Club.

20-year-old Keys has been enjoying the best season of her career, breaking into the top 20 in rankings. She will need to continue her good form against Radwanska, and keep the unforced errors to a minimum. Radwanska will be the first seeded player that Keys has faced, and she must step up her level significantly. The Pole will eat her up if she produces too many errors. Either way, the match will be in the young American’s hands, as she will be the one dictating play with her power.

Prediction: Keys moves on to her second major semifinal of the year, winning 6-4, 4-6, 6-4.