Yarra Valley Classic: Serena Williams Sizzles With 6-1, 6-4 Win Over Tsvetana Pironkova

Serena Williams continued her impressive Australian Open preparations with a straight-sets thrashing of Tsvetana Pironkova Wednesday even as top-ranked Ashleigh Barty struggled. Williams, 39, has been in belligerent form at the Yarra Valley Classic and overpowered the Bulgarian with a 6-1, 6-4 victory in 74 minutes. "So far, so good. It's special to play here with what's going on in the world," said Williams, who only lost four games against Daria Gavrilova in her opener on Monday. Williams, aiming for a record-equalling 24th Grand Slam title at the Australian Open, broke Pironkova first up and kept her foot on the gas with 25 winners and six aces.

The American will play world number six Karolina Pliskova or compatriot Danielle Collins in the quarter-finals.

Barty, however, was pushed to the brink, but avoided an early exit at Melbourne Park.

World number one Barty also had a fright in her match against Marie Bouzkova of the Czech Republic, but recovered from a second-set stutter to win 6-0, 4-6, 6-3.

"Mid-match I lacked execution... but happy to get it on my terms in the end," Barty said after a quick turnaround, having beaten Ana Bogdan in straight sets on Tuesday night.  

Barty, hoping to break her country's 43-year singles title drought at the Australian Open, will face Shelby Rogers of the United States next.

Reigning Australian Open champion Sofia Kenin was also pushed hard by American Jessica Pegula, dropping the first set and finding herself 4-1 down in the second  before prevailing 5-7, 7-5, 6-2. 

"I was happy the way I was able to change things in the second set... I found my groove," said Kenin, who will play Garbine Muguruza next in a rematch of last year's Australian Open final. 

World number five Elina Svitolina also had to come from behind to beat 2017 French Open champion Jelena Ostapenko 6-7 (7/4), 6-3, 6-2.

She'll next face 20th-ranked Belgium's Elise Mertens, who knocked out Caroline Garcia of France 7-6 (7/1), 6-3. 

But world number two Halep, like Williams, bucked the trend and downed Laura Siegemund in straight sets to set up a Gippsland Trophy quarter-final against Russia's Ekaterina Alexandrova, who upset French Open champion Iga Swiatek 6-4, 6-2.

"I'm really happy with both matches, so it's good to be back," said Halep.