While most of the celebrities in New York City were attending various Mercedes Benz New York Fashion Week festivities, stars like Natalie Portman, Charlize Theron, and Tobey Maguire were over at the US Open watching Roger Federer beat Andy Murray.

Miss Portman, joined by a girlfriend, looked adorable in her red, blue, and yellow dress as she made her way to the tournament, smiling for the paparazzi.

Meanwhile, Charlize Theron and her longtime boyfriend Stuart Townsend seemed unsure of where to place their attention- on each other, or on the tennis match? They publicly displayed their affection for each other throughout the afternoon.

And Tobey Maguire was also spotted enjoying the day, sporting a shaved-down coif. In the end, Federer emerged victorious, winning three-straight sets 6-2, 7-5, 6-2. It was his fifth straight US Open championship, and 13th Grand Slam title.

Gossip Girls

Enjoy the pictures of Natalie Portman and Charlize Theron at the US Open (September 8).