It was an action-packed day, with some of Monday's matches being pushed to Tuesday. Many big names stayed in contention while a former champion saw her run end early. These are the Top 5 photos from Melbourne. (All Photos Getty Images.)

1

After the grueling ATP Cup, Rafael Nadal is showing no signs of fatigue. The Spaniard rolled to a 6-2, 6-3, 6-0 victory against Hugo Dellien, hitting 38 winners and only making 21 errors in a two-hour match. 

2

Dominic Thiem boosted his head-to-head record to 8-0 after dismissing Adrian Mannarino 6-3, 7-5, 6-2. The Austrian wasn't afraid to step in and control points from the beginning of the match. Thiem will next face Australia's Alex Bolt. 

3

For the fourth consecutive year, Donna Vekic advanced into the Australian Open second round. Vekic defeated former world No. 1 Maria Sharapova, 6-3, 6-4, to continue marching towards the event's second week—which she has yet to appear in.

4

Madison Keys is moving on  after posting a 6-3, 6-1 score over Russia’s Daria Kasatkina. The American reached the Brisbane final before heading to Melbourne, and seems to be bringing the same energy and form to the new week.

5

Nick Kyrgios put on a show in front of his home crowd in Melbourne. The Aussie eased past Lorenzo Sonego, 6-2, 7-6 (3,) 7-6 (1), to set up a second-round clash with Frenchman Gilles Simon. Kyrgios defeated Simon last season in Washington, D.C.