The NASCAR world suffered a tremendous loss before Sunday’s Cup Series Championship.

Joe Gibbs Racing co-founder Coy Gibbs died unexpectedly on Saturday night, the company announced Sunday afternoon.

He was 49 years old. A cause of death was not immediately announced.

Gibbs, the son of co-owner Joe Gibbs and father of Xfinity Series winner Ty Gibbs, was at Phoenix Raceway on Saturday to witness his son’s championship run.

“I’ve always got his back as his father,” Coy said on Saturday. “… Watching it today, just to see his determination … it definitely made me proud. It made my wife — we were both proud, just because he hammered down and did his job. If he wants to do this for a living, he’s going to learn how to do that.”

A former Stanford football player and NFL assistant coach for Washington, Gibbs followed in his father’s footsteps, moving from football into the racing ranks as a driver before moving into the boardroom as an executive.

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Ty was slated to participate in Sunday’s Cup Series race, driving in the No. 23 car for 23XI Racing. However, once news filtered through about his father’s passing, the company announced that Ty would not race. Xfinity Series driver Daniel Hemric will fill in for Ty in the No. 23 car.

The racing world shared its condolences for the Gibbs family, as well as its memories of Coy, described by longtime NASCAR chairman and CEO Jim France as a “true racer and friend.”

Gibbs is survived by his wife, Heather, sons Ty, Case, Jett, and daughter Elle. His nephew, Jackson, will change tires for Christopher Bell’s No. 20 championship car in Sunday’s race.