Playoff drivers Joey Logano and William Byron led the way in opening Monster Energy NASCAR Cup Series practice at Dover.
Logano was fastest in the first of two Friday practices at 163.221 mph (22.056 seconds). Byron was second quick at 162.133 mph.
Third quickest was 11-time Dover winner Jimmie Johnson at 161.834 mph. Ryan Blaney (P) was fourth at 161.507 mph, and Alex Bowman completed the top five at 161.067 mph. Bowman ran the most laps in practice at 50.
The rest of the top 10 were Paul Menard at 160.995 mph, Denny Hamlin (P) at 160.471 mph, Kurt Busch at 160.385 mph, Aric Almirola at 159.638 mph, and Kyle Larson (P) at 159.088 mph.
Playoff drivers outside the top 10 were Kevin Harvick 11th at 158.940 mph, Martin Truex Jr. 12th at 158.821 mph, Chase Elliott 13th at 158.110 mph, Kyle Busch 15th at 157.680 mph, Clint Bowyer 18th at 157.487 mph, and Brad Keselowski 19th at 157.226 mph.
Elliott is the defending race winner. Truex won at Dover in the spring.
Kevin Harvick was quickest in the best 10 consecutive lap average over Jimmie Johnson, Ryan Blaney, Alex Bowman, and Paul Menard.
There were no incidents in practice. There are 38 cars entered in the Drydene 400.
UP NEXT: Final practice at 3:35 p.m. ET.