Chase Briscoe hopes to defend his race title in Phoenix on Sunday.

NASCAR heads to Arizona for the fourth race of the 2023 season with Sunday’s United Rentals Work United 500 at Phoenix Raceway.

Chase Briscoe is the defending champion, but that doesn’t automatically put him among this year’s pre-race favorites. In addition to having no top-20s so far this year, Briscoe will be driving a race car that features a significantly different competition package from his 2022 victory.

Rules changes designed to enhance racing on tracks of 1.058 miles or shorter and on road courses — exceptions being high-banked concrete Bristol and Dover — means this year’s cars at Phoenix Raceway will produce roughly 30 percent less downforce.

The height of the rear spoiler has been halved from 4 inches to 2 inches, and the number of downforce-producing devices underneath the car (diffuser strakes, engine panel strakes and the diffuser’s outer fencing) has been reduced significantly.

To allow teams to adjust to these changes, NASCAR added a 50-minute practice session on Friday afternoon.

“I think any time you can have less downforce, it’s going to bring the cars closer together and create a better race,” Briscoe said. “The tires wear out, and you start slipping and sliding around. It just makes it more competitive. There’s good and bad to that.

“It means, as a team, we have to be on it if we want to have a chance at a win, but if you can hit your setup right and keep track position, then it just adds that much more excitement. I don’t know that we can take much from last year because of the changes that have been made, so we’ll have to see what happens when we get on track for practice.”

Chevrolet drivers have won the first three races of the current season, but it remains to be seen how they’ll fare with the new competition package on Sunday. In addition to Briscoe, Kevin Harvick, Ryan Blaney, Kyle Busch, Joey Logano and Ross Chastain each posted a pair of top-10 finishes in Phoenix last year.

UNITED RENTALS WORK UNITED 500The Place: Phoenix Raceway

The Date: Sunday, March 12, 2:30 p.m. CT

Defending Champion: Chase Briscoe

TV: FOX

Radio: SiriusXM NASCAR (Channel 90)

Distance: 500 miles

NASCAR Wire Service contributed to this story