Last July, Muguruza - who was still a teenager at the time - had to undergo ankle surgery, putting her rapid rise up the rankings on hold and sending her out of action the rest of the year. After a six month leave from the tour nobody really knew what to expect - but the now-20-year-old Spaniard has gotten off to a flying start to 2014, starting with a quarterfinal run at her comeback event in Auckland, her first WTA title in Hobart and, now, reaching her first Grand Slam second week at the Australian Open.
There was no secret to her strategy against the No.10-seeded Wozniacki - she seemed determined to hit through her opponent's rock solid defense, ripping serves and groundstrokes from start to finish. While they weren't landing as consistently in the first half of the match, Muguruza kept at it, and after sneaking out the second set the momentum was hers, and she moved through by a 46 75 63 scoreline.
"I know Caroline is a great player and a great fighter. I was really prepared for a big fight today," Muguruza said. "The key was to be strong mentally, especially in the third set, because we were both playing so well. To be strong and to just keep fighting was what made the difference for me."
Muguruza's win over the No.10-ranked Wozniacki was the third Top 10 win of her career, after a pair of wins over World No.9s in Miami the last two years - Vera Zvonareva in 2012 and Wozniacki in 2013.
"It's a great win," Muguruza commented. "It's not the first time I've won against a Top 10 player, but it's amazing to win on center court against a Top 10 player like Caro. So I'm really happy now."
Wozniacki, who will fall out of the Top 10 after this tournament now, was disappointed but gracious.
"I had quite a lot of chances," Wozniacki said. "I won the first set; was up in the second. I had break points in the last three games she was serving, I think. Not the last one, but I had chances to get away there and probably should have closed the match. Sometimes you just don't take your chances.
"I thought she played some great tennis. She's definitely a good player. She has beaten good players before. She's on a roll right now. I think we'll be seeing a lot of her in the future, definitely."
"I was very happy I could come back in the second set," Radwanska said afterwards. "Of course the first set was pretty close - I think I just slowed down a little bit at the end of the first set - but I was thinking that I had to keep playing my game in the second set, and it got a little bit easier from there."
Radwanska beat Muguruza in the pair's only previous meeting, at Miami in 2012.