Harvick piloted the JR Motorsports No. 88 to a best lap of 174.961 mph on the 2-mile track. The winner of the last two Sprint Cup Series events is scheduled to make his third XFINITY start of the season in Saturday’s Drive4Clots.com 300 (4 p.m. ET, FOX Sports 1).

Denny Hamlin, driving the Joe Gibbs Racing No. 54 Toyota in place of the injured Kyle Busch, landed the second-fastest lap at 174.681 mph. Brad Keselowski was third-fastest at 174.338 mph in the Team Penske No. 22 Ford as Sprint Cup Series regulars claimed the top three spots in the 57-minute opening session, which was extended two minutes by a pair of caution periods for debris.

Regan Smith drove the JR Motorsports No. 7 Chevrolet to the fourth-best lap at 173.842 mph, and Erik Jones completed the top five in another Gibbs Toyota at 173.829 mph.

Defending series champion Chase Elliott scraped the outside wall midway through first practice, scuffing the side of his No. 9 Chevy. His JRM crew worked on making minor repairs and it did not appear that it would deploy a backup car. He managed the seventh-fastest lap in limited practice time, completing just five laps in the early session.

Series points leader Ty Dillon was 17th-fastest among the 36 drivers to participate in opening practice as his Richard Childress Racing crew worked on the right-rear springs on the No. 3 Chevrolet.

Final XFINITY Series practice is scheduled Friday at 6 p.m. ET.

Results: Practice 2

Austin Dillon was able to unseat his former Richard Childress Racing teammate Kevin Harvick as the fastest among the XFINITY Series entries in final practice at Auto Club Speedway on Friday.

Harvick led the opener, but Dillon’s 174.914 mph in the second session topped the field, with the No. 88 of the reigning Sprint Cup Series champion coming into the garage fourth at a 173.632 mph clip. The pair sandwiched Brad Keselowski (174.740 mph) and Regan Smith (173.758 mph) with fellow Childress entry Brendan Gaughan rounding out the top five at 173.490 mph.

Reigning champion Chase Elliott was seventh on the board at 173.360 mph, while Denny Hamlin, filling in the for the injured Kyle Busch in the No. 54 Toyota, was eighth at 173.235 mph.

Mike Bliss dropped oil on the track ahead of Ryan Reed and Kyle Larson, spinning both the No. 16 of Reed and No. 42 of Larson out. Larson’s team indicated that they would be switching to a backup Chevrolet Camaro. Larson completed just four laps and finished 22nd at 169.723 mph, while Reed made just one circuit for a 168.508 mph clip and 25th position.

The incident caused a red flag for track cleanup that lasted roughly 20 minutes.

Tune in Saturday at 12:45 p.m. ET for Coors Light Pole Qualifying on FOX Sports 1 and the Drive4Clots.com 300 at 4 p.m. ET, also on FOX Sports 1.

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Since Daytona, Elliott has registered two fifth-place finishes and a seventh-place showing. He will attempt to run for his fourth consecutive top 10 in Saturday’s Drive4Clots.com 300 at Auto Club Speedway in Fontana, California (4 p.m. ET on FOX Sports 1).
 
Elliott remains fond of the two-mile track where he finished sixth last season in his first-ever start there.
 
"It’s such a blast to race at Auto Club," he said. "There are so many different grooves drivers run, and that’s what makes it so exciting. You may see four-wide as we fan out on restarts during Saturday’s race.
 
"If you’re a race fan, this is a must watch, no question about it."
 
Next weekend, Elliott will make his long-awaited NASCAR Sprint Cup Series debut at Martinsville Speedway, but first he must focus on defending his XFINITY Series title. The No. 9 NAPA AUTO PARTS Chevrolet driver ranks fourth in the standings, 25 points behind leader Ty Dillon.
 
He hopes to close in on Dillon with a visit to Victory Lane.
 
"The West Coast swing has been a good two weeks," Elliott said. "We are looking to close on a high note this weekend in California. A win would do that."

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