Photos from Flushing Meadows: Day 6

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

What part of Nicole Gibbs hit this shot, her racquet or her ponytail? The American lost to Flavia Pennetta, but leaves the Open with her first two Grand Slam victories.

Pennetta bounced back quickly from a slow start. Her good draw continues: She’ll play Casey Dellacqua next.

“Sometimes you’re up, sometimes you’re down,” Petra Kvitova said after her defeat to 145th-ranked Aleksandra Krunic, thus making the only assessment of her game you’ll ever need to read.

Kvitova also said that the athletic Krunic got to “almost” every ball, and she wasn’t exaggerating.

“You know, I don’t know my limits,” Krunic said afterward. “Today I think I pushed myself to my total limits.”

And then she invented a new victory celebration: The spinning ponytail.

Victor Estrella Burgos in...defeat? The 34-year-old Dominican had the tournament of his life.

Andy Murray in...victory? He advanced to a highly-anticipated fourth-round match with Jo-Wilfried Tsonga.

Novak Djokovic’s team was happy with his quick win on Saturday; they obviously had a tee time to make.

Novak obliged, then obliged the fans with a ball.

Serene Serena on her way to a straight-set win over Varvara Lepchenko.

Not-so-serene Serena needed some self-motivation.

Serena looked ready to fight the sky yesterday. This wasn’t even match point...

Genie Bouchard won her second straight match by identical 6-2, 6-7, 6-4 scores.

Barbora Zahlavova Strycova let us know how she felt. After every point.

But she played well enough to push Bouchard to the limit.

Bouchard let out a bigger scream than usual in victory. “I’ve never felt anything like it,” she said of the Arthur Ashe experience.