Hamlin won the first of three key summer races with his victory in Michigan. It precedes a monumental milestone this weekend for NASCAR: the first international points-paying race since 1958. The Cup Series grid travels to the Autódromo Hermanos Rodríguez road course in Mexico City for the Viva Mexico 250 on June 15.
The Cup races in Michigan, Mexico City and Pocono Raceway are crucial to NASCAR’s inaugural in-season challenge.
There haven’t been many significant changes to the structure of the Cup Series calendar since the implementation of the playoffs starting in 2004. While NASCAR first introducted a postseason in 2004 with playoffs that have undergone a few changes over the past two decades, this marks the first in-season competition with a tournament held over five races culminating in the Brickyard 400 at Indianapolis Motor Speedway on July 27.
It’s rare to have a new in-season event in the Cup Series. There’s a lot to know about it and we’ve got you covered:
What is the NASCAR in-season challenge?
It is a single-elimination tournament across five races, beginning with the June 28 race at Atlanta Motor Speedway, that includes the top 32 drivers in the Cup Series championship standings following the June 1 race at Nashville Superspeedway.
Those 32 drivers will be up in a bracket and seeded by their best results from the Cup races at Michigan, Mexico City and Pocono. Tiebreakers are the next-best finish from those three seeding races. Drivers advance by finishing higher than their opponent in the bracket.
Each of the five races will cut the field in half, similar to March Madness in college basketball. There will be 32 drivers in contention in the first race, then 16 for the second, eight for the third, four for the fourth and two drivers facing off for the win in the fifth and final race.
NASCAR in-season challenge contestants
The 32-driver field is set. Here’s who will be contending in NASCAR’s first in-season challenge (car number in parentheses):
(24) William Byron, Chevrolet
(5) Kyle Larson, Chevrolet
(20) Christopher Bell, Toyota
(11) Denny Hamlin, Toyota
(9) Chase Elliott, Chevrolet
(45) Tyler Reddick, Toyota
(12) Ryan Blaney, Ford
(22) Joey Logano, Ford
(1) Ross Chastain, Chevrolet
(23) Bubba Wallace, Toyota
(19) Chase Briscoe, Toyota
(48) Alex Bowman, Chevrolet
(2) Austin Cindric, Ford
(17) Chris Buescher, Ford
(8) Kyle Busch, Chevrolet
(60) Ryan Preece, Ford
(77) Carson Hocevar, Chevrolet
(47) Ricky Stenhouse Jr., Chevrolet
(16) AJ Allmendinger, Chevrolet
(21) Josh Berry, Ford
(71) Michael McDowell, Chevrolet
(42) John Hunter Nemechek, Toyota
(34) Todd Gilliland, Ford
(43) Erik Jones, Toyota
(38) Zane Smith, Ford
(3) Austin Dillon, Chevrolet
(54) Ty Gibbs, Toyota
(99) Daniel Suarez, Chevrolet
(7) Justin Haley, Chevrolet
(10) Ty Dillon, Chevrolet
(4) Noah Gragson, Ford
(6) Brad Keselowski, Ford
NASCAR in-season challenge prize
The winner of the inaugural in-season challenge will take home $1 million.
NASCAR in-season challenge races, schedule
The five races of NASCAR in-season challenge are:
June 28: Quaker State 400 at Atlanta Motor Speedway
July 6: Grant Park 165 at the Chicago Street Course
July 13: Toyota/Save Mart 350 at Sonoma Raceway
July 20: Autotrader EchoPark Automotive 400 at Dover Motor Speedway
July 27: Brickyard 400 at Indianapolis Motor Speedway
How to watch the NASCAR in-season challenge
TNT will be broadcasting all five of the in-season challenge races with a secondary broadcast on truTV focused on the specific bracket matchups. Here’s how to watch all of them:
Stream NASCAR in-season challenge races on Sling
Quaker State 400
Date: June 28, 2025
Time: 7 p.m. ET
Location: Atlanta Motor Speedway in Hampton, Georgia
TV: TNT, truTV
Stream:Sling TV, WatchTNT
Grant Park 165
Date: July 6, 2025
Time: 2 p.m. ET
Location: Chicago Street Course in Chicago
TV: TNT, truTV
Stream:Sling TV, WatchTNT
Toyota/Save Mart 350
Date: July 13, 2025
Time: 3:30 p.m. ET
Location: Sonoma Raceway in Sonoma, California
TV: TNT, truTV
Stream:Sling TV, WatchTNT
Autotrader EchoPark Automotive 400
Date: July 20, 2025
Time: 2 p.m. ET
Location: Dover Motor Speedway in Dover, Delaware
TV: TNT, truTV
Stream:Sling TV, WatchTNT
Brickyard 400
Date: July 27, 2025
Time: 2 p.m. ET
Location: Indianapolis Motor Speedway in Speedway, Indiana
TV: TNT, truTV
Stream:Sling TV, WatchTNT