Cathleen Driscoll has spent her career preparing for a moment like this. 👏 Cathleen and Idalgo will take on the field of 40 athletes tomorrow night under the Florida lights in the $750,000 Rolex US Equestrian Open Grand Prix. 📺 Catch this combination Saturday at 8:15 PM/ET on USEF Network #rolex | #USAJumping | #USEqOpen