Biffle and Truex Jr. finish second and third in 100-minute session
RELATED: Learn more about the Sprint Showdown
MORE: Full practice results
Austin Dillon topped the lone practice for Friday night's Sprint Showdown (7 p.m. ET, FOX Sports 1, MRN, SiriusXM) at Charlotte Motor Speedway.
Dillon turned a fast lap of 189.288 mph at the 1.5-mile track during the 100-minute session.
Greg Biffle (188.910 mph) was the second-fastest in the session, followed by Martin Truex Jr. (188.798 mph).
The Sprint Showdown consists of two segments of 20 laps each, with the winner of each segment advancing to Saturday night's NASCAR Sprint All-Star Race. The winner of the first segment will not race in the second segment.
Biffle has not missed an All-Star Race since 2004. Truex Jr. is currently second in the Sprint Cup Series point standings with 10 top-10 finishes in the first 11 events, but has not qualified for the NASCAR Sprint All-Star Race.
Paul Menard (188.758 mph) and Danica Patrick (188.613 mph) rounded out the top five in Friday's practice.
Clint Bowyer, who won last year's Sprint Showdown, finished seventh in practice.
Chase Elliott, who has made two Sprint Cup starts this season, finished 10th in practice (187.533 mph) and logged the most laps (53) in the session. Elliott is attempting to give Hendrick Motorsports five cars in the field for the NASCAR Sprint All-Star Race on Saturday night (9 p.m. ET, FOX Sports 1, MRN, SiriusXM). He is also slated to compete in this weekend's NASCAR XFINITY Series 3M 250 at Iowa Speedway.
Qualifying for the Sprint Showdown will take place at 4:15 p.m. ET Friday on FOX Sports 1. It will be a two-round session, with the opening round being 20 minutes and the top 12 advancing to the second round for a five minute session to determine the top 12 starting spots.