Serena Williams moves to the quarterfinals at the Australian Open. It wasn’t an easy ride through, since Serena had to work around a bunch of errors to beat Barbora Strycova. [Feature Image by EW.com]

The No. 16-ranked Barbora made the No. 2-ranked Serena sweat it out, engage in more and longer rallies and turn her win into a struggle.

With this win Serena remains on track in her effort for an Open-era record 23rd Grand Slam title. If she gets there, the six-time Australian Open champion would surpass Steffi Graf. Besides the fact, she will regain the number one ranking as well.

Next up, she’ll face No. 9 Johanna Konta, who beat Ekaterina Makarova for the second straight year in the fourth round.

“It was a really good match for me, and I’m glad I got through it,” Williams said in her on-court interview.

“It’s good to know I have a Plan B, or an Option 2,” said Williams, the No. 2 seed and a 22-time major winner. “It’s always good to have something to improve on, and I know I can do better on my serve.”