Australian Open 2012 Schedule: Jan. 19 TV Schedule, Matches and Bracket Guide

It's on to Day Four at the Australian Open. By the time the day's action is over, the second round for both men's and women's singles will be in the books.

In the men's bracket, we've already seen Rafael Nadal and Roger Federer advance to the third round, as Nadal topped Tommy Haas in straight sets and Federer advanced via walkover. Day Four will determine if world No. 1 Novak Djokovic and world No. 4 Andy Murray will get to join them.

The women's bracket saw world No. 1 Caroline Wozniacki and defending Australian Open champ Kim Clijsters advance in Day Three. Maria Sharapova, Serena Williams and assorted other big-name players will attempt to join them in Day Four.

If you're wondering where and when you can watch the day's action, you've come to the right place. Read on for a full breakdown of everything you need to know.

Watch: Tennis Channel, ESPN2, ESPN3.

When: The Tennis Channel will begin its coverage of Day Four at 7:00 p.m. ET on Wednesday. ESPN2 will take over at 11:00 p.m. ET and continue until 7:00 a.m. ET on Thursday. Matches can also be seen on ESPN3.com.

Notable Men's Matches

Novak Djokovic (1) vs. Santiago Giraldo – Third Match at Rod Laver Arena

Lleyton Hewitt vs. Andy Roddick (15) – Fifth Match at Rod Laver Arena

Ricardo Mello vs. Jo-Wilfried Tsonga (6) – Second Match at Hisense Arena

Andy Murray (4) vs. Edouard Roger-Vasselin – Fourth Match at Hisense Arena

Full Schedule for Day Four available at the Australian Open's official website.

Notable Women's Matches

Jamie Hampton vs. Maria Sharapova (4) – First Match at Rod Laver Arena

Barbora Zahlavova Strycova vs. Serena Williams (12) – Second Match at Rod Laver Arena

Carla Suarez Navarro vs. Petra Kvitova (2) – Third Match at Hisense Arena

Vera Zvonareva (7) vs. Lucie Hradecka – First Match at Margaret Court Arena

Full Schedule for Day Four available at the Australian Open's official website.

Men's Storylines

It would be an utter shock if Santiago Giraldo gave Novak Djokovic any trouble, but keep an eye on Andy Murray against Edouard Roger-Vasselin. Murray got off to a rough start against Ryan Harrison in the first round, so he'll be looking for a good bounce-back performance.

Andy Roddick's match against Lleyton Hewitt will also be worth watching. With Mardy Fish out of the picture, Roddick is the highest-ranked American man still standing at the Open. It's going to be interesting to see how long he lasts.

Women's Storylines

Maria Sharapova looked dominant in the first round against Gisela Dulko, and the same is true of Serena Williams against Tamira Paszek. Both of them will look to advance with ease.

Whatever you do, don't sleep on Petra Kvitova. She got off to a slow start against Vera Dushevina in the first round, but then won 12 straight games to take the match in straight sets.

Men's Bracket: Full breakdown available at Australian Open's official website.

Women's Bracket: Full breakdown available at Australian Open's official website.