Gary Gaines, a Texas high school football team who got featured in the "Friday Night Lights" franchise, died. He was 73.

Gaines' bereaved family confirmed the heartbreaking news through a statement to Associated Press. They did not disclose Gary Gaines' cause of death exactly, but they said that he passed away after his long battle with Alzheimer's disease.

He learned about the tragic diagnosis in 2017.

The Alzheimer's Association explains that the disease is a type of dementia that affects a patient's daily tasks due to worsening symptoms. It directly damages ones thinking and behavior, and even leaves lasting effects on a person's memory.

It comprises 60 percent to 80 percent of dementia cases, per the website.

Gaines' family has not confirmed details about the coach's funeral. Amid the trying times, they received heartfelt support from Gaines' friends and colleagues who paid tribute to him.

Former Permian assistant, Ron King, told Odessa American that he could not find the exact, proper words to remember Gaines' life.

"It's a big loss for the coaching profession. There are a lot of coaches he took under his wing and mentored," he told the outlet, via New York Post.

Gary Gaines' Legacy Explored

The outpouring love and support of the public are not surprising as Gaines was a good man to everyone throughout his life.

Gaines famously got featured in Buzz Bissinger's book, "Friday Night Lights: A Town, a Team and a Dream." The book was then adapted into a film version in 2004, which starred Billy Bob Thornton.

Before his death, he had a fruitful 30-year coaching career. Among the teams he worked on, he notably had a four-year stint at Odessa Permian, leading the program in the field.

In 1988, however, Permian lost in the state semifinals following James "Boobie" Miles's absence. The running back suffered a knee injury that kept him from playing with the team.

But the following year, Gaines made a huge comeback by leading Permian to the six state championships. After the triumph, he bid his goodbye to become an assistant coach at Texas Tech.

Gaines also served Permian's rivals, Abilene High and San Angelo Central, and became their coach. He waited for a few more years before serving Abilene Christian as a coach before his retirement in 2012.