In parts of West Texas, there are more pump jacks than people. There are towns where the train no longer stops and where downtowns are all but dried up.

Petersburg, Texas, with a population of roughly 1,200, is one of those towns. Over the last few decades, Petersburg has lost most of its industry and many of its people.

But there is one thing it won't let go of: its beloved Buffaloes, the high school football team. At the afternoon pep rally, nearly the whole town showed up.

This is Texas, after all, and in Petersburg, as elsewhere in the Lone Star State, the local team has a proud tradition.

But pride will only get you so far, especially when you have just 78 students in your high school.

The team has found a way to compete by literally "shrinking" the football game: It plays a shorter game with four 10-minute quarters, on a shorter field where the 40-yard line is midfield.

The most noticeable difference? Each team fields only six players. Traditional football has 11. Most of the kids play offense and defense and are on the field the entire game.

Running back Kearby Garza likes the having more field time.

"If you love the game, you are going to want to be in it and able to play," he said.

Six-man football moves a lot faster than a regular game and there's much more scoring. On a recent night, Buffaloes star player Blake Smith scored five touchdowns.

Smith, basically the team's quarterback and running back, touted the advantages of the six-man game.

"There is more room to make plays and everything is not cluttered up, so when you get more room ... there are bigger hits, people with better moves," he said. "It's just more exciting."

Petersburg's rival for its homecoming game was a team from Meadow, Texas -- an even smaller town with a population of just 600.

Petersburg 'Back in the Game' With a Six-Man Team

The teams sometimes have to drive three or four hours just to find another six-man team to play. But no matter how far they go, their fans follow.

"If you were a robber and we had an away game, you would sure come here and clean up because the doors are shut and everything is locked up," said Buffaloes coach Joseph O'Malley. "We are gone and town is vacant."

The community revolves around its school, he said.

"I think if, for some reason, this school was to disappear, I really think the town would soon follow," he said.

O'Malley -- a six-man specialist -- came to Petersburg five years ago after the town made what turned out to be the excruciating decision to shrink its Buffaloes from an 11-man to a six-man game.

One look at the school's trophy case shows why the move was tough and necessary: For decades, Petersburg was a powerhouse, but its last state championship was in 1963.

With a meaner, leaner six-man team, the coach said the school is back in the game.

"We have the empty case here at the end, and what we are trying to do is let the kids see the empty trophy case is unfinished business," O'Malley said.

Today, Petersburg football players are confident in the six-man set-up. Some aren't sure they could win a game fielding an 11-man team.

"I don't think we would be able to stand with the big boys," said Smith.

But for Petersburg High School to be standing at all, it takes a lot of work that starts at the top: Coach O'Malley is also Principal O'Malley.

"There are not enough hours [in the day] and I wouldn't recommend this to just everybody," O'Malley said. "It is a unique situation."

He's not the only one multi-tasking.

At half-time of the homecoming game, look carefully and you will see a few members of the marching band wearing football jerseys. Players sometimes have to pick up instruments because you can't have football game without a half-time show.

Practice presents another challenge. To scrimmage in six-man, you need 12 kids.

"Sometimes you have to ad lib," O'Malley said. "Dads and granddads and aunts and uncles that came up to watch practice found themselves getting pulled out of the stands to come stand and hold the dummy or do this or that. And pretty quick, the visitors at practice became less and less."

But there are more and more fans in the stands now, including, recently, two members of Petersburg's last state championship team in 1963 and two sisters who were cheerleaders for the team in the 1970s.

"We are all like a big family. It doesn't matter what year, when you graduated, you come back for this," one of the sisters said. "This is Petersburg."

Petersburg won its homecoming game. They finished the season with ten wins and two losses. It was a victory not just for a team, but for a town that's lost a lot over the years but isn't ready to lose its Friday nights.

Watch the full story on "Nightline" tonight at 11:35 p.m. ET.