2011 US Open champion Sam Stosur beat Kristina Mladenovic 6-2, 6-2 at the Citi Open and became only the seventh active woman on tour to reach 500 career wins. She is also the last woman to beat American Serena Williams at the US Open, who is trying to achieve the Calendar Grand Slam at Flushing Meadows this year.

Stosur commented on Serena Williams’s attempt to achieve the Grand Slam this year at the US Open, winning all four majors in the same calendar year.

It’s incredible what she’s trying to achieve. Four in a row, going for five in a row for the Calendar, she deserves all of the accolades that go along with it. She’s the greatest player of our generation by far, and one of the greatest of all-time.”

The Australian has one of the best records against Williams on tour, with three total wins, and two wins in Grand Slams. She dominated the American in straight sets, 6-2, 6-3 at the 2011 US Open final to win her sole Grand Slam title. She says that she matches up well against Williams, and has a chance upset her again this year.

I’ve actually quite enjoyed playing Serena, it’s a great challenge and I know I’ve got a game that troubles her. I’ve got those kind of weapons that can bother her. I know that on any given day, I know that I can win.”

Stosur was asked if she could give any advice to the rest of the field on how to beat Serena, “Tennis is a lot about matchups. I match up well against her. There is a lot of pressure going into the US Open for her. She is not immune to the nerves and pressure.”