An officiating blunder helped decide the final American Conference playoff spot, the NFL admitted in a statement on Monday.
A four-month quest for a playoff berth came down to the final seconds of the last regular-season game for the San Diego Chargers, who needed a win or draw with Kansas City to qualify or lose the spot to the Pittsburgh Steelers.
With eight seconds remaining in the fourth quarter on Sunday at San Diego, the Chiefs' Ryan Succop attempted a 41-yard field goal that went wide of the left upright.
But the Chargers' defensive unit lined up improperly on the play, video evidence showed after the game, although the violation went unnoticed on the field.
"On the play, San Diego lined up with seven men on one side of the snapper. This should have been penalised as an illegal formation by the defence," the NFL said in a statement.
No more than six players can be on the line on either side of the centre when the ball is snapped under NFL rules.
"The penalty for illegal formation by the defense is a loss of five yards," the NFL said. "This is not subject to instant replay review. Had the penalty been assessed, it would have resulted in a 4th-and-7 from the San Diego 18 with four seconds remaining, enabling the Chiefs to attempt a 36-yard field goal."
Had the correct call been made, Succop would have had a second chance at the winning kick in regulation.
Instead, the game went into overtime and the Chargers won 27-24 to capture the final playoff spot.
They will play a first-round clash on Sunday at Cincinnati.
Had the Chiefs won, the Pittsburgh Steelers would have been playing at Cincinnati instead.
