Gaines said he resigned from the West Texas football program he helped make famous. He said he doubts he'll coach again but wasn't sure what's next for him.
"We're going to give it to someone else and, hopefully, they can make more out of it than we did," Gaines said. "We came here to make some deep playoff runs and we weren't able to do that. That's what (Permian fans) expect, and I expect as well."
He leaves with a 69-28-1 record in eight years as Permian's head coach, including a 23-21 mark in his last four years. In all, he coached Permian from 1986-89 and 2009-12, and was an assistant there for three years in the early 1980s.
His second stint in Odessa included a lone playoff victory and no district championships.
Gaines led the program to a state 5A championship in 1989. The Panthers were undefeated that season, just a year after H.G. "Buzz" Bissinger spent a year in town researching his best-seller, which chronicled how high school football binds an oil patch community.
Todd Veseley, athletic director of the Ector school district, said it would be a "daunting" task to replace Gaines. He declined to say whether he asked Gaines to step down following the Panthers' disappointing 5-6 season.
"Any time anyone the quality of coach Gaines leaves, it leaves a vacuum," he said.
Gaines would not say directly whether he was asked to resign.
"It was just one of those things," he said. "I understand when programs don't improve sometimes the head coach has to bear that responsibility."
Made into a movie in 2004, Bissinger's book was a hit everywhere but Odessa. Locals felt Bissinger betrayed their hospitality by writing about the sociological woes surrounding the team and town, including allegations of racism and a win-at-all-costs mentality. An NBC television series with the same name was less about football than the community depicted.
After leading the Panthers to the state title more than 20 years ago, Gaines left Permian to become linebackers coach at Texas Tech. He left coaching in 2005 after five years at Abilene Christian to return to Odessa as the school district's athletic director. Two years later, he moved north to take a similar post in Lubbock.
The once-vaunted Panthers have won six state titles but none since 1991.
Before Gaines' return in 2009, the Permian program enjoyed something of a revival, making it to three regional finals the previous four seasons while compiling a 38-11 record under Darren Allman, a former Permian player and Gaines protege who left in 2009 to take the coaching job at Austin Westlake.