For the 2010 postseason, the NFL installed a modified sudden death system to determine the winner when the score is tied at the end of regulation. Beginning in 2012, the system has been expanded to cover all NFL games, including regular-season and preseason games.

Teams have the opportunity to possess the ball at least once in the extra period unless the team that receives the overtime kickoff scores a touchdown on its first possession. The changes are meant to aid competitive fairness while adding a wrinkle of additional strategy for head coaches.

"We felt this proposal gave us the opportunity to make a pretty good rule even better," says Atlanta Falcons President/CEO and Chairman of the NFL Competition Committee RICH MC KAY. "I really believe the more you talk about the issue, the more you understand the statistics, the more you say there must be a change."

Here's a look at the NFL's overtime procedures:

Preseason And Regular Season

At the end of regulation time, the referee will immediately toss a coin at the center of the field in accordance with rules pertaining to the usual pregame toss. The captain of the visiting team will call the toss prior to the coin being flipped.

Following a three-minute intermission after the end of the regulation game, there shall be a maximum of one 15-minute period. Each team must possess or have the opportunity to possess the ball unless the team that has the ball first scores a touchdown on its initial possession.

Play continues in sudden death until a winner is determined, and the game automatically ends upon any score (by safety, field goal, or touchdown) or when a score is awarded by the referee for a palpably unfair act. Each team shall be entitled to two timeouts, and if there is an excess timeout, the usual rules shall apply. The try is not attempted if a touchdown is scored. Disqualified players are not allowed to return.

If the score is tied at the end of the 15-minute overtime period, the game shall result in a tie.

Instant Replay: No challenges. Reviews to be initiated by the replay official.

Postseason

At the end of regulation time, the referee will immediately toss a coin at the center of the field in accordance with rules pertaining to the usual pregame toss. The captain of the visiting team will call the toss prior to the coin being flipped.

Following a three-minute intermission after the end of the regulation game, play will be continued in 15-minute periods until a winner is declared. Each team must possess or have the opportunity to possess the ball unless the team that has the ball first scores a touchdown on its initial possession.

Play continues in sudden death until a winner is determined, and the game automatically ends upon any score (by safety, field goal, or touchdown) or when a score is awarded by the referee for a palpably unfair act. Each team has three time outs per half and all general timing provisions apply as during a regular game. The try is not attempted if a touchdown is scored. Disqualified players are not allowed to return.

Instant Replay: No challenges. Reviews to be initiated by the replay official.

Key Definitions

Possession:

Actual possession of the ball with complete control. The defense gains possession when it catches, intercepts, or recovers a loose ball.

Opportunity to possess:

The opportunity to possess occurs only during kicking plays. A kickoff is an opportunity to possess for the receiving team. If the kicking team legally recovers the kick, the receiving team is considered to have had its opportunity. A punt or a field goal that crosses the line of scrimmage and is muffed by the receiving team is considered to be an opportunity to possess for the receivers. Normal touching rules by the kicking team apply.