The 133rd U.S. Open begins today. As one of the oldest tournaments in American sports history, the U.S. Open not only serves as a finale to Grand Slam season but gives our country a chance to put on a show for tennis enthusiasts around the world. That's right, FOH with the strawberries and cream and bring in the Grey Goose carts!

Aside from all the day drinking, there actually is some world class action to catch on the courts. After all, we know you're going to find yourself checking out a possible Novak Djokovic/Rafael Nadal match-up or simply checking out Serena Williams. So, find out which player won the first "open era" tournament, how a serve once killed a line judge, and more in 20 Things You Didn't Know About the U.S. Open.