Day 6 of the Australian Open features the final matches of the first week; can Serena Williams and Karolina Pliskova ascend? Plus, Caroline Wozniacki's battle against No.9 seed Jo Konta.
WTA Staff

MELBOURNE, Australia - It's the last day of the first week, and the final third round matches are slated to take place at the 2017 Australian Open.

We preview all the day's biggest matchups right here on wtatennis.com.

Saturday, Third Round

[2] Serena Williams (USA #2) vs Nicole Gibbs (USA #92)
Head-to-head:
Serena leads,1-0
Key Stat:
Gibbs matches her best-ever Grand Slam finish in Melbourne (2014 US Open). 

Former World No.1 Serena Williams has looked strong as she faced down tough opposition in the first two rounds. Standing between her and the second week is countrywoman Nicole Gibbs, who hasn't dropped a set in wins over No.25 seed Timea Babos and Irina Falconi.

The trend reverses what was a tough start for the Stanford alum, who won just five games in her first two WTA main draw matches of the season. Coming up against a battle-tested 22-time Grand Slam champion, Gibbs will need to rely on every ounce of her ability to pull off the upset.

As for Serena, the No.2 seed shook off a disappointing loss at the ASB Classic and has shown signs of steady improvement in wins over Belinda Bencic and Lucie Safarova. The six-time Australian Open champion hasn't lost before the fourth round in Melbourne since 2006.

[17] Caroline Wozniacki (DEN #20) vs [9] Johanna Konta (GBR #9)
Head-to-head: First meeting
Key Stat: Wozniacki is aiming to reach the second week Down Under for the first time since 2013.

One of the most anticipated match-ups of the third round will take place on Margaret Court Arena, as 2016 semifinalist Konta takes on former World No.1 and 2011 semifinalist Wozniacki. The Dane has been on a tear since the start of the US Open last summer, rocketing up the rankings from a low of No.74 all the way back into the Top 20.

Konta, by contrast, has shown off the kind of consistency for which Wozniacki herself was once best known, starting off the season with a win at the Apia International Sydney, and rides a seven-match winning streak into her first meeting against the No.17 seed.

Can the Brit continue to back her talent against such experienced opposition?

[5] Karolina Pliskova (CZE #5) vs Jelena Ostapenko (LAT #38)
Head-to-head:
Pliskova leads, 1-0
Key Stat: Ostapenko is currently enjoying her best run at a Grand Slam.

Pliskova has been ruthless through two wins in Australia, dropping just six games against Sara Sorribes Tormo and Anna Blinkova. Her first real test of the tournament could come from Ostapenko, a talented 19-year-old who blasted No.31 seed Yulia Putintseva off the court behind 28 winners.

Ostapenko has enjoyed her share of highs and lows since transitioning onto the WTA tour back in 2015, and the former Wimbledon junior champion is into the third round at a Grand Slam for the first time. The fiery teenager will likely have her work cut out for her against the placid Pliskova, who is trying to reach the second week of a major for just the second time after emphatically ending the 17-Slam streak at the 2016 US Open.

Who will emerge victorious in the battle of big hitters?