Last year, the USTA took viewers behind the scenes at its training headquarters around the nation (from Florida to California). The consensus: Being a pro is a lot of hard work from sunrise to sunset.

Pro appearances in the feature include Alison Riske, Christina McHale, Nicole Gibbs, Sam Querrey, Donald Young and many, many more.

"A lot of times you see the end result for the best players. you see them holding trophies you see them winning these great matches," former No. 1 Lindsay Davenport says in the clip. "But you don’t see the 8-10 hours a day each day that they spend trying to get ready for that moment."

Most of the players in the clip have done very well this year, and only time will tell where these pros and others American rising stars' hard work will pay off next.