"Inside the Winner's Circle, Presented by Keeneland" is a series showcasing graduates of the Keeneland September sale who have gone on to achieve success on racing's biggest stages. When Covfefe (Into Mischief) arrived at Brad Cox's barn at the Fair Grounds to begin training for her 2019 campaign, the trainer could have circled just about any race on his calendar. He had a talented, fast, well-bred filly and might have entertained thoughts of trying the GI Kentucky Oaks. But what makes Cox one of the fastest rising stars in his...