Kentucky Derby entrant Mendelssohn trains along with an outrider at Churchill Downs Thursday, May 3, 2018, in Louisville, Ky. The 144th running of the Kentucky Derby is scheduled for Saturday, May …

Kentucky Derby entrant Mendelssohn trains along with an outrider at Churchill Downs Thursday, May 3, 2018, in Louisville, Ky. The 144th running of the Kentucky Derby is scheduled for Saturday, May 5. (AP Photo/Charlie Riedel)