#22-Ryan Blaney was fastest during opening practice at Dover with a speed of 154.275mph.
The rest of the top 10: #20-Erik Jones, #9-William Byron, #7-Justin Allgaier, #3-Ty Dillon, #48-Brennan Poole, #42-Tyler Reddick, #18-Daniel Suarez, #19-Matt Tifft, and #1-Elliott Sadler..
37 drivers practiced during the session.
See complete results on the Dover practice 1 speeds page (pdf).
