Kevin Spacey
The House of Cards actor oohed and aahed from the stands on Day 2.
Andre Agassi
The tennis legend walked the red carpet on Day 2.
Vera Wang, Anna Wintour & Jewel
The fashion designer and Vogue editor posed with the singer on Day 1. "Had fun singing and sharing my story here at the US Open w a special group of people who have come together to help raise money for at risk youth," Jewel wrote on Instagram.
Serena Williams
The top-seeded American beat Russian Ekaterina Makarova in a 6-3 6-3 victory on Day 2.
Leslie Odom Jr. & Phil Collins
The Hamilton star and the living legend jammed at the USTA Foundation Gala on Day 1.
Novak Djokovic
The Serbian sportsman defeated Poland's Jerzy Janowicz 6-3, 5-7, 6-2, 6-1 on Day 1. But, Djokovic called a medical timeout after the fifth game. "It was just prevention. It's all good. It's getting better and better each day," he said of his wrist injury. "Hopefully as the tournament progresses, I'll reach my peak."
Debra Messing & Alec Baldwin
The actors had the audience in stitches at the USTA Foundation Gala on Day 1. "Had a ball control-hosting th @USTA_Foundation with my pal @AlecBaldwin & to meet its Chairman @JRBlake," Messing tweeted.
Emeril Lagasse
The famous chef suited up for Day 1. "Happy to be a part of the #USOpenGala benefitting the @USTA_Foundation! #ServingUpDreams," Lagasse tweeted.
Emilia Bechrakis & Ryan Serhant
The couple attended the USTA Foundation Gala on Day 1. "The @usta_foundation gala is always an inspiring one where we come together to raise money to help provide children with brighter futures through tennis and education," Serhant wrote on Instagram. "My wife @emilia_bechrakis and I are proud supporters and honored to be in the presence of such brilliant minds, friends, role models and clients. Thank you to our dear friend and attorney Y. David Scharf for inspiring us to give back to the community!!!"