"Not much went wrong for me today," Tomljanovic, who had never even beaten a Top 25 player, said after her win over the World No.3. "I'm obviously very happy, but I don't want to get too happy about it."
"After seeing the first two seeds go out, you kind of feel like you can do it, too," Tomljanovic added. "I grew up with these girls who beat them. I went on the stadium for the first time, and I knew she kind of feels at home there, because she's been there a lot more than I have. But I went out there and inside I really, really thought I could win the match today. I think that showed, and that's why I won."
There was one more upset, though there was definitely an asterisk on that one - No.19 seed Sam Stosur took out No.9 seed Dominika Cibulkova, 6-4, 6-4. It was a surprise based on seedings but the head-to-head was a good predictor - Stosur had won all four of their previous meetings in straight sets.
Sharapova leads Stosur in their head-to-head, 13-2, including a 3-0 record on clay courts.
"Even today I knew I had a good head-to-head, but you certainly don't take anything for granted," Stosur said. "I knew Dominika was going to come out there and try and change that, and that's exactly what I will try and do against Sharapova. And I've beaten her before - I know what it takes. I know I'll have to play very well against her. I know there are certain things I have to do well.
"I will just go out there and certainly give it my best shot."
"Despite my record against her and my victory against her a few weeks ago, this is a new match," Sharapova said. "I'm sure she's ready for the match against me, and so will I. I look forward to that challenge. She has a great serve, she uses the court extremely well, and she moves very well on it.
"It's a good match-up. I look forward to it."
Other matches saw No.8 seed Angelique Kerber beat No.31 seed Daniela Hantuchova, 7-5, 6-3, No.14 seed Carla Suárez Navarro beat American wildcard Taylor Townsend, 6-2, 6-2, No.18 seed Eugenie Bouchard rally from 5-3 down in the first set to beat Johanna Larsson, 7-5, 6-4, Garbiñe Muguruza beat Anna Schmiedlova, 6-2, 6-4, and French wildcard Pauline Parmentier rally from 5-3 down in the third set to beat Mona Barthel, 1-6, 6-1, 7-5, and reach the first Grand Slam second week of her career.