Tom Kreager | The Tennessean

The first day of high school football practice begins Monday for Tennessee teams across the state.

With that comes new rules set by the National Federation of State High School Associations, which locally teams competing in the TSSAA must follow.

Here is a breakdown of the key changes fans can expect to see in 2019.

Redefined scrimmage formation

Offenses no longer have to have seven players on the line of scrimmage. The rule change is to allow a situation where a play can be run if there are 10 players on the field.

The new rule stipulates six people can be on the line of scrimmage with four in the backfield as long as five of the players on the line are offensive linemen with traditional numbering.

"You can now run a play if that 11th guy is not on the field," TSSAA assistant director Richard McWhirter said.

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No tripping, please

Tripping the runner is now illegal. You can't trip anyone now whereas in the past you couldn't trip anyone but the runner.

The penalty is an illegal conduct and costs the team 15 yards.

Horse collar

The horse collar rule has been adapted. A defender can no longer grab an opponent by the jersey's back name plate and pull him down.

In the past, the hand had to be inside the jersey or shoulder pads.

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"Now it's a penalty if you grab the back of the shirt with motion," McWhirter said. "That's illegal with a 15-yard penalty."

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40-second clock

Tennessee was given permission by the NFHS to experiment with the 40-second play clock in 2018.

The TSSAA asked permission because McWhirter felt that it would soon be required. And he was right. NFHS has passed the 40-second play clock for all states.

Jersey numbers

By 2024, all numbers on uniforms will have to be a solid color. Teams are being made aware now for when they start to order new uniforms.

Currently numbers can be the same color as the jersey with a different color outlining it, which can make them difficult to identify.

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