Kerber came to Indian Wells on the heels of a three-match losing skid, all of those losses coming in straight sets too - to Ekaterina Makarova in the fourth round of the Australian Open and then back-to-back opening round losses at Doha and Dubai, against Mona Barthel and Roberta Vinci, respectively.
But on Saturday the No.4-seeded German got back on track with a 63 62 victory over Irina-Camelia Begu, and on Monday she continued that pattern, cruising through the first set then rallying from 4-1 down in the second set and winning a tie-break to beat No.30 seed Yanina Wickmayer, 61 76(4).
How did Kerber turn the second set around? "My coach came to me and just told me to remember my game plan, which we had before the match," she said. "I just had to keep focusing on my game, playing point by point and believing in my game. It really helped me. I'm happy I could make it."
Kerber is feeling the confidence again. "It's for sure better right now," she said. "Before coming here I wasn't sure about how my back would feel after my matches, but now it's much better and my confidence is of course back and I feel good, and I'm looking forward to playing tomorrow again."
The 4-1 second set deficit to Wickmayer wasn't the only curveball thrown at Kerber on Monday - there was an earthquake at Indian Wells during the day, before Kerber took the court for her match.
"I felt it," Kerber commented. "I was talking with my coach in the garden and everything was shaking. In the first moment we were both thinking it was maybe a subway, but actually we are in the desert, so no way that there's a subway. But yeah, I felt it - it was the first time I've ever felt an earthquake."
Next up for Kerber is Spanish qualifier Garbiñe Muguruza, who followed up three set wins over Bojana Jovanovski and No.17 seed Ekaterina Makarova in her previous two rounds with a 64 60 win over Magdalena Rybarikova, reeling off 10 games in a row from 4-2 down in the first set to beat the Slovak.
Muguruza has had some success against Top 10 players - in just her second WTA main draw match at Miami last year she beat then-World No.9 Vera Zvonareva, 64 63, a win that actually put her in the history books as the equal-fastest player in WTA history to beat a Top 10 player. Back at the 1981 US Open, Andrea Leand also beat a Top 10 player in her second WTA main draw match - Andrea Jaeger.
Kerber and Muguruza will be playing against each other for the first time.