Photos from Flushing Meadows: Day 4

The greatest doubles team of all time came to the Grandstand yesterday...

​Each day during the U.S. Open, we'll feature Anita Aguilar's photography, captioned by Steve Tignor. For more photo galleries, click here.

The tennis teachers said “get low,” and at some point Genie Bouchard listened.

And when they said "follow through all the way," she was still listening.

Serbian qualifier Aleksandra Krunic braved a pro-American crowd in Armstrong to come back and beat Madison Keys.

Krunic put everything into it, including her ponytail...

...and her braces.

“You look really upset” a concerned reporter told Madison Keys in her press conference afterward. She couldn’t hide her devastation. “When it really mattered,” she said, “I didn’t play well.”

Ana Ivanovic was, as usual, a pro in defeat.

Novak Djokovic went the full gumby for this one in his straight-set win over Paul-Henri Mathieu.

Then he stopped the match and said, “And now we dance.”

Serena Williams had little trouble beating the wind, and her opponent.

Wimbledon champ Petra Kvitova, who won without her best on Thursday, is keeping her eye on another Grand Slam prize.

CoCo Vandeweghe’s snarl was worse than her bite, as she fell in straights to Carla Suarez Navarro.

Suarez Navarro shows how to start one of the game’s prettiest shots.

Nick Kyrgios showing off his not-so-secret weapon in a straight-set win over Andreas Seppi.

The greatest doubles team of all time came to the Grandstand yesterday...

...and won in three sets.

“Uh, going after Williams doesn't seem to be working."

Zarina Diyas had the United States against her when she faced 15-year-old CiCi Bellis, but she held her nerve and won in three.

Bellis gave it another wallop...

....but came up a set short. Later, she put the last three days of her life in proper teenage perspective: "It was mind-blowing, actually."