No wonder they sipped champagne from their trophies after clinching their third consecutive major doubles title on Sunday at Roland Garros.
"Just so everyone knows, we have our trophies here. We have a little champagne in it. It's tradition to drink champagne out of the trophy, so I'm going to do so," Mattek-Sands said during a press conference before raising her trophy in the air and clinking it against that of her teammate.
Their win in Paris was their second at Roland Garros after they claimed the title in 2015, and their fifth Grand Slam title overall.
Safarova and Mattek-Sands began playing together only two years ago and have been dominating women's doubles recently. Mattek-Sands is the No. 1-ranked doubles player with Safarova holding the No. 2 spot.
The secret behind their chemistry? Just relaxing and enjoying themselves on the court.
"We are taking it one match at a time. Really, we kind of enjoy our practice days. We enjoy our off days," Mattek-Sands said. "We're playing singles, doubles. I played mixed doubles here. I think the moment is enough, actually."
They won two titles this year, the Australian Open and Charleston, and also claimed the U.S. Open last year. If they win at Wimbledon, they will simultaneously hold all four major titles.
"It's funny, because we don't even kind of think about it that way," Mattek-Sands said. "It's kind of tough to even look back and to the future to what you could do and what you have done. But we're really excited for grass. We're looking forward to Wimbledon. We love playing on grass. We are going to be ready there, too"
Barty and Dellacqua were bidding for their first Grand Slam title after reaching three major finals in 2013.