Another day in the NASCAR antitrust trial and another revelation. This time, executive vice president John Probst was on the stand. The sanctioning body has begun its defense today after 23XI Racing and Front Row Motorsports wrapped up their side of the case this morning.

John Probst serves as the Chief Racing Development Officer for NASCAR and was called up as their first witness in the trial. He oversees things like changes to the Next Gen car. All of the flaps and shark fins and fixing the rear clip in the last few years, Probst works on that.

As Chief Racing Development Officer, Probst knows a lot of details about the Next Gen car. That includes how much NASCAR spent researching and developing the Gen 7 car.

According to Adam Stern of Sports Business Journal, Probst says it cost $14 million total to research and develop the car. He also said that the teams had no part in the design process.

John Probst says that @NASCAR has spent about $14 million in total on research and development around the Gen 7 car, and when asked if teams helped design any of the parts of the car, he responded: “No.”

➡️ He said wind-tunnel testing costs teams about $60,000 to $70,000 a day.

— Adam Stern (@A_S12) December 10, 2025

In the last few years, practice time has been reduced heavily compared to previous generations of NASCAR. Wind-tunnel testing is one of the few things that teams are able to do to test new setups and find more speed. However, it is clearly cost-prohibitive at $60,000 to $70,000 a day, as Probst testified.

NASCAR trial: Next Gen car one of teams’ complaints

The Next Gen car is one of the key points in 23XI and Front Row’s argument. Particularly, the single-source parts. Prior to the Next Gen car, teams built their own chassis or bought them from a manufacturer of their choice. The cars were built from the ground up by the teams with whatever parts they wanted to use that fell within the regulations and rules that NASCAR had set.

So, that’s a major change. On top of that, NASCAR owning the intellectual property of the car and design of the car is restrictive as well. At least, that’s how the teams see it. The jury will decide which argument they believe is most credible. For those who have issues with the Next Gen car, you probably know whose side you’re on in the NASCAR trial. But we will see how the jury feels in a few days.

NASCAR believes that they can finish up arguments by Friday. Whether we hear closing arguments on Friday remains to be seen. Judge Bell wanted to finish up by Friday, and thanks to both sides speeding things along, it just might.

For a more in-depth look at the NASCAR trial, check out this interview with Rakesh Kilaru, an attorney with Wilkinson Stekloff. Kilaru has extensive experience in these cases and provided great insight into the process of these trials. He also touched on how it could play out if the teams win.