MELBOURNE -- The last time Madison Keys played Yaroslava Shvedova, Keys wound up lying on the grass in tears. Forced to retire from her third-round match at Wimbledon in 2014 with an injured left thigh, she was distraught.
On Thursday in the second round at the Australian Open, Keys lost the first set and was dealing with a toe injury that required medical treatment. But there were no tears this time. She recovered to beat Shvedova 6-7 (4), 6-3, 6-3 in 2 hours, 2 minutes.
"I think, first of all, I have to start putting the ball on the court at the beginning," Keys said of her slow start. "I didn't think I was doing that very often."
She recovered, thanks to her superb groundstrokes, particularly her forehand, which produced 20 winners. Her play improved as the match wore on, and she lost only six points on her serve in the final set.
Keys, 21, had her finest performance at a major here last year when she reached the semifinals. She lost to Serena Williams, but they are in different halves of the bracket this year.
Keys faces a stiff challenge in the third round against 2008 French Open champion Ana Ivanovic, currently ranked No. 20.
Ivanovic advanced in the first match of the day with a 6-3, 6-3 win over Anastasija Sevastova after a lengthy delay when medical personnel rushed to help a spectator who had fallen on the stairs in the upper level of the 15,000-seat stadium. The players stayed on the court during the break, getting regular updates from tournament officials. Tournament organizers said the spectator was treated in the stadium before being taken by stretcher for observation and more treatment.
Garbine Muguruza, another up-and-coming star, also advanced.
Just 22 years old, she already has been a Wimbledon runner-up and the No. 3 seed at the Australian Open. On Thursday, she took care of Kirsten Flipkens with a comfortable 6-4, 6-2 win to reach the third round at the season's first major.
Muguruza, a Spaniard whose idols growing up were Williams and Pete Sampras, is not afraid to play first-strike tennis. Against Flipkens, she hit 23 winners in the routine victory.
"It's a great win," Muguruza said. "I know Kirsten. I played against her two times before, and I knew it was going to be like a complicated match, because she doesn't have the common style of other [women] on the tour. So I'm pretty happy about my performance, yeah."
With No. 2 Simona Halep out of the tournament, Muguruza is the highest seed in her half of the draw. Further, she wouldn't have to face Williams, Maria Sharapova or a red-hot Agnieszka Radwanska until the final.
Azarenka is a two-time Australian Open champion, but it has been three years since she has hoisted the Daphne Akhurst Memorial Cup.
"Whatever happens to you kind of leads you towards whatever moment is going to happen," Azarenka said. "For me, what I found interesting for me is that it was going the wrong way. You know, I had injuries. I had not much of luck happening. I wanted to look and assess what it is I can do better, what it is I can improve.
"First was getting healthy and then trying to just enjoy. It comes pretty natural, but it did require a lot of self-work and really start kind of accepting myself for failures that I had. And really just accept those and move forward, try to see what I can do better."
Azarenka has won all seven of her matches in 2015 and hasn't dropped a set. In her Aussie opener two days ago, Azarenka completed the career Grand Slam double bagel with a 6-0, 6-0 thumping of Alison Van Uytvanck.
Azarenka will next play Naomi Osaka, who upset No. 18 Elina Svitolina 6-4, 6-4. No. 19 Jelena Jankovic and No. 30 Sabine Lisicki also lost. In all, 17 women's seeds have gone down so far, the most at the Australian Open since 2006.
Information from The Associated Press was used in this report.