Clemson's Travis Etienne (9) returns the opening kickoff in the first half of the Sugar Bowl on Jan. 1, 2018. The NCAA has made several rules changes, including some to help limit injuries incurred during kickoffs. (AP Photo/Gerald Herbert) Credit: Gerald Herbert | AP

According to the National Football Foundation, the kickoff return is the play that yields the highest risk of head injuries.

For that reason, one of this year’s college football rule changes is designed to discourage teams from returning kickoffs.

“It’s about player safety,” said University of Maine head coach Joe Harasymiak.

Under the new rule, if a player calls for a fair catch on a kickoff inside his 20-yard line, the ball will be placed at the 25-yard line just as if the kicker had kicked it into the end zone and it wasn’t returned, resulting in a touchback.

A National Football Federation release pointed out that some kickers have mastered the “pooch” kick, purposely kicking it high and shorter and sometimes angling it into a corner to force the opponent to return it. Under the old rule, if a kick returner called for a fair catch, the ball would be placed at that spot.

“That’s going to be interesting. You’re going to have to make good decisions (based on the kick),” Harasymiak said.

The NCAA football rules committee also has eliminated all blocks below the waist if they take place more than five yards beyond the line of scrimmage. It also clarified where you can block below the waist.

Linemen who are inside the tackle box at the snap may block below the waist from the front or the side until the ball leaves the tackle box. The tackle box is the area that extends laterally between the offensive tackles on either side of the line.

All other players may block below the waist only if the force of the block is directly from the front.

If a player is outside the tackle box or in motion at the snap, he may not block below the waist even if the block is directed from the front. And once the ball has left the tackle box, no player is allowed to block below the waist toward his own end line.

“That will affect triple-option teams more,” said Harasymiak.

Another rule to enhance player safety requires pants to have knee pads and to completely cover the knee. In recent years, players’ pants have been getting shorter, exposing knees to increased risk of injuries.

In other new rules, if a defense commits a personal foul or unsportsmanlike conduct penalty during a field goal, the kicking team can accept the three points if it makes the attempt and the defensive team also will be assessed the penalty on the ensuing kickoff.

Under the previous rule, the kicking team could accept the penalty and take the points off the board or take the points but not have the penalty assessed to the defensive team.

There is also a rule intended to speed up the game and reduce the length of games.

This year, a 40-second play clock will be used to shorten the time between the touchdown and extra-point attempt and between the kickoff return and the first play from scrimmage. There previously was a one-minute break.