Overview
- The Championship 4 features Denny Hamlin and Chase Briscoe for Joe Gibbs Racing and William Byron and Kyle Larson for Hendrick Motorsports, with the highest finisher among them taking the Cup title.
- Joe Gibbs Racing attributed recent Martinsville engine DNFs to a faulty batch of valve springs and says it has a mitigation plan, as Hamlin chases a first championship with a series-best six wins this season.
- Caesars Sportsbook lists Hamlin as the betting favorite for Phoenix, and teams plan to use Friday’s extended practice window that permits wholesale setup changes.
- NASCAR is evaluating playoff format changes for 2026 after renewed criticism, including Kevin Harvick’s warning that a one-race decider can misalign with season-long performance; no changes affect this weekend.
- Sunday’s race ends Phoenix’s six-year run as the fixed finale before the championship rotates to other tracks, while dominant seasons by Xfinity’s Connor Zilisch and Trucks’ Corey Heim face the same one-race deciders.