Philpott is an experienced spotter who has been around the NASCAR paddock at various points this season, serving stints with Reaume Brothers Racing and Joey Gase Motorsports in the Truck Series and Xfinity Series this year alone.
He was also Martin Truex Jr.'s spotter for the Daytona 500 at the start of this year, although that race ended early for the long-time Cup Series veteran.
Meanwhile, Keselowski will have regular spotter TJ Majors out of action this weekend and for the next month or so as he recovers from a medical procedure, as he revealed on Dale Earnhardt Jr.'s podcast.
"I missed Darlington. I've got a little procedure coming up this week, and I'll be out for probably about a month," Majors told the NASCAR legend.
"Hopefully, I'll be back for good after that and not have to worry about it anymore."
Both Bell and Keselowski are former winners of the Coca-Cola 600, with the former taking his first victory in the iconic race just last year and among the favorites to go to victory lane again this weekend.