CoCo Vandeweghe came to the Australian Open unseeded and under the radar, but all of that changed after a fortnight in Melbourne.

“I think I don’t shy away from a challenge necessarily,” she said after reaching her first Grand Slam semifinal. “I never have. Growing up, I’ve always just been wanting to prove people wrong in a lot of different regards.”

The 25-year-old American started the 2017 season with the goals of reaching a major semifinal and a quarterfinal at a major besides Wimbledon, where she reached the last eight in 2015. By the end of the tournament, she’d achieved all that and more, including a Top 20 debut after knocking out defending champion Angelique Kerber and French Open winner Garbiñe Muguruza in back-to-back straight set matches.

“I’m very happy with starting the year this way, putting validation to the hard work that I’ve put in in the off-season, the sacrifices, all the good stuff like that.

“But, you know, at the same time I’m not satisfied. Like I said, I mean, there’s a disappointment factor because I’m not satisfied. I think that’s a good thing.”

Looking to build on her major breakthrough, Vandeweghe is your Breakthrough Player of the Month!

Final Results for January’s WTA Breakthrough Performance Of The Month

1. CoCo Vandeweghe (50%)
2. Elise Mertens (28%)
3. Katerina Siniakova (16%) 
4. Lauren Davis (6%)

2016 Breakthrough Performance Of The Month Winners

January: Zhang Shuai
February: Jelena Ostapenko
March: Nicole Gibbs
April: Cagla Buyukakcay
May: Kiki Bertens
June: Elena Vesnina
July: Kristina Kucova
August: Karolina Pliskova
September: Naomi Osaka
October: Peng Shuai

How it works:

Finalists are selected by wtatennis.com
Winner is then determined by a fan vote on wtatennis.com