Just as Peyton Manning prepares to lead the Denver Broncos into the Super Bowl, one Colorado school district has barred kids from wearing the future Hall of Famer's jersey - even though they are free to don rival Cam Newton's.

Manning's No. 18 could be used to show loyalty to the local "18th Street Gang, according to officials at Greeley-Evans School District 6, which operates 25 schools serving more than 21,000 students. That makes it one of six numbers identified by the distrcit as having potential gang associations.

“Gangs use those items of clothing for a few reasons,” school district spokeswoman Theresa Meyers told The Tribune, of Greeley. “They use them to recruit and they use them to intimidate.”

“Gangs use those items of clothing for a few reasons. They use them to recruit and they use them to intimidate.”

- Theresa Meyers, district spokeswoman

Other numbers that can't be worn by students in the public district, about an hour from the Bronco’s Mile High Stadium, are 13, 14, 31, 41 and 81.

But the No. 1 sported by Newton, quarterback of Denver's Super Bowl foe the Carolina Panthers, won't draw a flag.

Manning has worn No. 18 since his collegiate days at University of Tennessee, and his jersey has been a big seller in Colorado since he became a Bronco in 2012.

But even with the Broncos in Sunday’s NFL championship, and schools around the state holding “Broncos Days,” Greeley-Evans hasn’t had to field any real complaints about its dress code.

“I think as time has gone on, it’s just an expectation,” Meyers said.  “Now, people are just like, ‘That’s the rule.’”