Rookie Jeb Burton was fastest during opening practice at a very hot Dover International Speedway on Thursday, with a speed of 152.066 mph. #29-Ryan Blaney was second, followed by: #51-Kyle Busch, #54-Darrell Wallace, Jr., #3-Ty Dillon, #94-Chase Elliott, #31-James Buescher, #8-Max Gresham, #17-Timothy Peters, and #98-Johnny Sauter in the top 10. 28 drivers practiced during the session. See complete results on the Dover practice 1 speeds page (pdf) .
