The U.S. Open overhauled its mixed doubles tournament in hopes of drawing the top singles players. The defending champions don’t intend to move out of the way so easily.

The US Open mixed doubles tournament has a new look, with huge names and prize money. Here's what you'll want to know.

Veteran doubles experience overcame singles stardom as defending champions Andrea Vavassori and Sara Errani reached the semi-finals at the U.S. Open's reimagined mixed doubles on Tuesday, as the event kicked off with a new format and new fans.