MELBOURNE, Australia – The second week continues at the Australian Open. On Day 8, can No.2 seed Serena Williams and No.5 seed Karolina Pliskova book two of the four remaining spots in the quarterfinals?

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

Monday, Fourth Round

[2] Serena Williams (USA #2) vs [16] Barbora Strycova (CZE #16)
Head-to-head: Serena leads, 2-0
Key Stat: Neither Serena nor Strycova have dropped a set en route to the second week.

Serena Williams saw her hopes of reclaiming World No.1 brighten when defending champion Angelique Kerber went out at the hands of CoCo Vandeweghe on Sunday. But before she can think of returning to the top of the WTA rankings, she’ll have to get past a fiery veteran in Barbora Strycova, who is in the fourth round of the Australian Open for a second straight year.

Strycova roared back from a 5-3 deficit in the second set, and will be looking to pull of the biggest upset of her career in her first encounter with the 22-time Grand Slam champion since 2012.

Serena has already dispatched former Top 10 players Belinda Bencic and Lucie Safarova along the way; can she continue to improve as Grand Slam No.23 draws closer?

[5] Karolina Pliskova (CZE #5) vs [22] Daria Gavrilova (AUS #26)
Head-to-head: Pliskova leads, 2-0
Key Stat: Pliskova is aiming for her second straight (and second career) Grand Slam quarterfinal.

Brisbane International champion Karolina Pliskova remains undefeated for the season, and takes on another young hopeful in Daria Gavrilova. The Aussie reached the fourth round Down Under for the second year in a row, winning a three-set thriller of her own against Timea Bacsinszky.

Pliskova showed few signs of vulnerability in her first two rounds, but found herself on the brink of defeat against Latvian youngster Jelena Ostapenko, who served for the match in the final set. Fresh off an early pick for best match of 2017, the No.5 seed is back in the second week of a major tournament and will look to widen her head-to-head advantage against Gavrilova, against whom she’s never dropped a set.

The 22-year-old has tended to save her best tennis for her adopted home soil; can she stun Pliskova and earn a career-best Grand Slam result?

Around the Grounds…

No.9 seed Johanna Konta renews her rivalry with No.30 seed Ekaterina Makarova, who pushed the Brit to an 8-6 final set at this very tournament one year ago. A battle of underdogs completes the fourth round line-up as qualifier Jennifer Brady takes on ageless wonder Mirjana Lucic-Baroni, who earned her best-ever result at the Australian Open at 34 years old.

The doubles tounament also continues in Melbourne, with No.2 seeds Bethanie Mattek-Sands and Lucie Safarova taking on Apia International Sydney champs Timea Babos and Anastasia Pavlyuchenkova, while top seeds Caroline Garcia and Kristina Mladenovic face No.13 seeds Katarina Srebotnik and Zheng Saisai in the third round.