NEW YORK, NEW YORK - AUGUST 30: Jose Reyes spectates a match on Day One of the 2026 US Open at USTA Billie Jean King National Tennis Center on Sunday, August 30, 2026 in Flushing, NY. (Photo by Michael Mooney/USTA via Getty Images)USTA via Getty ImagesDay 1 of Men’s Singles and Women’s Singles action at the 2026 U.S. Open got underway on Sunday at Flushing Meadows, N.Y, with plenty of notable celebrities in attendance.The matches for the 146th edition of the U.S. Open are once again taking place at the United States Tennis Association’s Billie Jean King National Tennis Center in Flushing Meadows, following the prestigious event’s annual Fan Week, which ran Aug. 23-29. Forbes$108 Million In Prize Money, 700,000 Honey Deuces Served: The 2026 U.S. Open By The NumbersBy Brett KnightThe U.S. Open, of course, is the fourth and final event in the annual Grand Slam of professional tennis following the Australian Open (January-February), the French Open (May-June) and Wimbledon (June-July).The U.S. Open’s 2025 Men’s Singles champion, Carlos Alcaraz, is back to defend his title, while 2024 and 2025 Women’s Singles champion Aryna Sabalenka has returned to vie for her third consecutive title. The 2026 U.S. Open, which offers $108 million in prize money, runs Sunday through Sunday, Sept. 13.Below are some of the celebrities spotted on the blue carpet and/or in the stands watching matches.ForbesHow To Watch The 2026 U.S. OpenBy Adam ZagoriaNEW YORK, NEW YORK - AUGUST 30: Jose Reyes spectates a match on Day One of the 2026 US Open at USTA Billie Jean King National Tennis Center on Sunday, August 30, 2026 in Flushing, NY. (Photo by Michael Mooney/USTA via Getty Images)USTA via Getty ImagesJosé ReyesNew York Mets star shortstop José Reyes attended Day 1 of the 2026 U.S. Open.NEW YORK, NEW YORK - AUGUST 30: Mike Colter in the stands during Day One of the 2026 US Open at USTA Billie Jean King National Tennis Center on Sunday, August 30, 2026 in Flushing, NY. (Photo by Michael Mooney/USTA via Getty Images)USTA via Getty ImagesMike ColterActor Mike Colter (Luke Cage, Plane, Evil) watched the action during Day 1 of the U.S. Open after walking the blue carpet at the event.NEW YORK, NEW YORK - AUGUST 30: Mike Colter arrives on the blue carpet during Day One of the 2026 US Open at USTA Billie Jean King National Tennis Center on Sunday, August 30, 2026 in Flushing, NY. (Photo by Michael Mooney/USTA via Getty Images)USTA via Getty ImagesNEW YORK, NEW YORK - AUGUST 30: Lindsey Vonn attends the US Open at the USTA Billie Jean King National Tennis Center on August 30, 2026 in New York City. (Photo by John Nacion/Getty Images)Getty ImagesLindsey VonnTeam USA Olympic gold medal-winning skier Lindsey Vonn walked the blue carpet ahead of Day 1 matches at the 2026 U.S. Open.NEW YORK, NEW YORK - AUGUST 30: Brandy Norwood poses for a picture on Day One of the 2026 US Open at USTA Billie Jean King National Tennis Center on Sunday, August 30, 2026 in Flushing, NY. (Photo by Michael Mooney/USTA via Getty Images)USTA via Getty ImagesBrandy NorwoodSinger and actress Brandy Norwood (Moesha, Cinderella, I Still Know What You Did Last Summer) settles into her seat after walking the blue carpet at Day 1 of Sunday’s matches.NEW YORK, NEW YORK - AUGUST 30: Brandy Norwood arrives on the blue carpet during Day One of the 2026 US Open at USTA Billie Jean King National Tennis Center on Sunday, August 30, 2026 in Flushing, NY. (Photo by Michael Mooney/USTA via Getty Images)USTA via Getty ImagesNEW YORK, NEW YORK - AUGUST 30: Kate Walsh attends the US Open at the USTA Billie Jean King National Tennis Center on August 30, 2026 in New York City. (Photo by John Nacion/Getty Images)Getty ImagesKate WalshActress Kate Walsh (Grey’s Anatomy, The Umbrella Academy) was among the celebrities walking the blue carpet before Day 1 matches at the U.S. Open.NEW YORK, NEW YORK - AUGUST 30: Danai Gurira arrives on the blue carpet during Day One of the 2026 US Open at USTA Billie Jean King National Tennis Center on Sunday, August 30, 2026 in Flushing, NY. (Photo by Michael Mooney/USTA via Getty Images)USTA via Getty ImagesDanai Guiria Actress Danai Guiria (The Walking Dead, Black Panther, Avengers: Endgame) walked the blue carpet ahead of matches at Day 1 of the U.S. Open.NEW YORK, NEW YORK - AUGUST 30: A guest and Breland during a Men's Singles match on Day One of the 2026 US Open at USTA Billie Jean King National Tennis Center on Sunday, August 30, 2026 in Flushing, NY. (Photo by Garrett Ellwood/USTA via Getty Images)USTA via Getty ImagesRapper, singer, songwriter and producer Breland (My Truck) and a guest attended a Men’s Singles match at the 2026 U.S. Open on Sunday.NEW YORK, NEW YORK - AUGUST 30: Adam Pally spectates a match during Day One of the 2026 US Open at USTA Billie Jean King National Tennis Center on Sunday, August 30, 2026 in Flushing, NY. (Photo by Michael Mooney/USTA via Getty Images)USTA via Getty ImagesActor Adam Pally (The Mindy Project, FUBAR) was in the stands on Day 1 of the 2026 U.S. Open on Sunday.NEW YORK, NEW YORK - AUGUST 30: Jeremy Culhane arrives on the blue carpet during Day One of the 2026 US Open at USTA Billie Jean King National Tennis Center on Sunday, August 30, 2026 in Flushing, NY. (Photo by Michael Mooney/USTA via Getty Images)USTA via Getty ImagesActor Jeremy Culhane (Saturday Night Live) walked the blue carpet ahead of the 2026 U.S. Open’s Day 1 matches.ForbesPhotos: Celebrities Attending Wimbledon 2026 Finals WeekendBy Tim Lammers