This time, Mattek-Sands teamed with Ram, a childhood friend from Wisconsin. They lost in the first round.
There was a time when the main tactic in mixed was picking on the woman. Not anymore, or at least not when the woman is a doubles specialist — such as Mattek-Sands, who in addition to Olympic gold has won nine Grand Slam titles between women's doubles and mixed.
"If they want to pick on me, I'm super pumped because I want someone to pick on me at net," Mattek-Sands said. "I love it."
A bigger issue might be how the men sometimes struggle to return women's serves, which come in at a different pace and from a different angle than they're used to.
"The girls have quite good sliders and it's a different ball than we see a lot of the times," said Ram, who won the mixed title at this year's Australian Open with Barbora Krejcikova. "There's two parts to it: one is the different ball and one is the fact that the guy is at the net causing some issues. So if you can manage that game, you usually do pretty well."