A leather-clad Gwen Stefani and her 6-month-old son Apollo take in the evening action between Roger Federer and Gael Monfils on Sept. 4. No word on whether her beaming smile has anything to with Federer's win.
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Hugh Jackman and wife Deborra-Lee Furness don't hide their excitement, getting into the Federer/Monfils spirit on Sept. 4 with a standing ovation.
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Ready for her close-up? Amy Schumer gets silly hanging out at The Moet amp Chandon Suite on Sept. 4.
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It appears former Gossip Girl actor Ed Westwick 'xoxo's tennis as he stoically watches the Federer/Monfils match on Sept. 4.
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ON THE SIDELINES
This man is mad for tennis! Mad Men star John Slattery sports his spectacles so he won't miss any of the Sept. 4 Federer-Monfils action.
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THE GOLD STANDARD
Olympian Lindsey Vonn knows a thing or two about athletic competition. The Gold medal winner puts on her game face on as one of the many A-listers at the Open on Sept. 4.
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Aww, what a 'match'! Ben Stiller and wife Christine Taylor put their heads together on Sept. 3 to see Andy Murray fall to Novak Djokovic.
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COULD IT BE?
Also watching Murray/Djokovic is Leonardo DiCaprio, who almost goes undercover on Sept. 3.
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One year after showcasing her engagement ring at the U.S. Open, Katie Couric and now-husband John Molner showcase their newlywed bliss while sitting courtside on Sept. 3.
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That's the spirit! Teen heartthrobs Ansel Elgort and Joe Jonas join forces on Sept. 3 – and lead the crowd in a bit of cheering.
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THE SMART STUFF
Jeremy Piven and Bridget Moynahan seem to have their thinking caps on on Sept. 3 while watching the evening action.
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Everybody say "cheese!" Luke Wilson gives fans a thrill with a snappy selfie on Sept. 2 during the windy evening matches.
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SIT BACK & RELAX
Also on hand on Sept. 2: Jesse Metcalfe and actress girlfriend Cara Santana, who look cool and casual while kicking back in the Moët amp Chandon suite.
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SNAP, CRACKLE, POP
Can you reach a little further, Josh? Groban goes to great lengths to oblige a fan with a photo from the Moët suite on Sept. 1.
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Country comes to the big city on Sept. 1 as Luke Bryan and his wife Caroline share some smiles from their seats.
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Mwah! Points for P.D.A.? Heidi Klum plants one on beau Vito Schnabel on Sept. 1.
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Taye Diggs gives a tip of the hat to the crowd on Sept. 1 while relaxing in the Moët amp Chandon suite with girlfriend Amanza Smith.
Seems like something good just happened! Josh Lucas is up in arms watching Maria Sharapova play from his spot in the Moët amp Chandon suite on Aug. 25.
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A TOUCH OF CLASS
Alec Baldwin and wife Hilaria are all dressed up on Aug. 25 for the opening night gala of the U.S. Open.
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IS IT 'LOVE'?
Model Karlie Kloss can't help but smile while hanging with businessman Joshua Kushner (Ivanka Trump's brother-in-law) on Aug. 25 during the opening night women's match, where Maria Sharapova defeated Maria Kirilenko.
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SONG & DANCE
Rock on! The opening night festivities end with a rousing performance by Fitz and the Tantrums at Arthur Ashe Stadium on Aug. 25.
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So who won? FOX & Friends anchors Brian Kilmeade, Elisabeth Hasselbeck and Steve Doocy enjoy a friendly match with Tennis Channel analyst Jim Courier on Aug. 25 outside FOX's Manhattan studio.
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THE MUSIC MAN
With guitar in hand, country star Hunter Hayes gets ready to rock out on Aug. 23 while performing during the Arthur Ashe Kids' Day festivities in Queens.
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Also at Arthur Ashe Kids' Day: pros Andy Murray and Serena Williams, who do some autograph-signing for the kids in the crowd.
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Novak Djokovic and fitness expert Shaun T work it out on Aug. 23 during Kids' Day.
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She's a triple threat! Actress, dancer and, apparently, deejay Julianne Hough mans the turntables on Aug. 21 at the Heineken U.S. Open Kick-Off Party at Manhattan's Dream Downtown hotel.
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Also partying with Heineken at the Dream: reunited Twilight stars Ashley Greene and Nikki Reed, who stay close while celebrating.
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IT'S A TOSS-UP
The most decorated doubles team in Grand Slam history, America's Mike and Bob Bryan, keep some balls in the air as Belarusian pro Victoria Azarenka looks on during an Aug. 21 visit to the Esurance Times Square Tennis event, which raised $100,000 for the V Foundation for cancer research.
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FOOD FOR THOUGHT
The Meatball Shop's Daniel Holzman and U.S. tennis player Sloane Stephens serve up something delicious on Aug. 21 during the annual Taste of Tennis gala at the W New York.
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FOUR OF A KIND
Now that's a hot ticket! New York Rangers goalie Henrik Lundqvist, tennis legend John McEnroe, actor Edward Norton and tennis star Novak Djokovic join forces on Aug. 21 for a charity match at Sportime on New York's Randall's Island, where Lundqvist and McEnroe took home a surprise win.
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THE LOW DOWN
She's got it! Venus Williams shows off her skills during an Aug. 21 visit to the FOX & Friends studios in Rockefeller Center.
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FIGURE IT OUT
Meanwhile, sis Serena Williams shows off her killer curves outside the Late Show with David Letterman's Ed Sullivan Theater on Aug. 20.
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Also visiting Letterman: newlywed Djokovic, who gives one perfect pose before heading into an Aug. 19 taping.
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SIGN OF THE TIMES
She comes in peace! Maria Sharapova serves up some Evian during a water delivery event at Bryant Park on Aug. 19.