What Patrick Mahomes was able to accomplish in the final 1:54 of regulation and overtime on Sunday night was incredible. Mahomes went 10 of 13 for 188 yards with two touchdowns and zero interceptions for the Kansas City Chiefs in their stunning 42-36 overtime victory over the Buffalo Bills in Sunday's AFC divisional round game.

While Mahomes was on another level at the end of the game and in overtime (5-for-5, 61 yards with a touchdown), Josh Allen was just as good as the Chiefs quarterback -- and didn't have an opportunity to get the ball in overtime. The NFL's overtime rule reared its ugly head once again as Mahomes' 8-yard touchdown toss to Travis Kelce ended the game.

The Chiefs needed just one possession to win the game, as a touchdown on the initial possession of overtime sealed the victory. To clarify, here are the postseason overtime rules (and why the Bills didn't get the ball back). 

  • Both teams have the opportunity to possess the ball at least once in overtime unless the team that receives the overtime kickoff scores a touchdown on its first possession (the Chiefs accomplished this against the Bills). The modified sudden-death overtime was instituted for the 2010 postseason. 
  • If the score is still tied at the end of an overtime period — or if the second team's initial possession has not ended — the teams will play another overtime period. Play will continue regardless of how many overtime periods are needed for a winner to be determined.
  • There will be a two-minute intermission between each overtime period. There will not be a halftime intermission after the second period.
  • The captain who lost the first overtime coin toss will either choose to possess the ball or select which goal his team will defend, unless the team that won the coin toss deferred that choice.
  • Each team gets three timeouts during a half.
  • The same timing rules that apply at the end of the second and fourth regulation periods also apply at the end of a second or fourth overtime period.
  • If there is still no winner at the end of a fourth overtime period, there will be another coin toss, and play will continue until a winner is declared.

If the Bills would have held the Chiefs to a field goal, overtime would have continued with the Bills having an opportunity to tie the game with a field goal or win it with a touchdown. The team that won the coin toss had the opportunity to win the game without the other team having the football on offense.

Allen called the toss and lost. Per StatMuse, Allen was 9-0 on calling the coin toss this season prior to Sunday -- and went 0-2 in the AFC divisional round loss to the Chiefs. 

What happened to the Bills on Sunday happened to the Chiefs in the 2019 AFC Championship Game, as Mahomes and the Chiefs' offense never touched the ball in overtime as Tom Brady led the New England Patriots to a 37-31 victory.

Whether the league will alter the overtime rules so both teams can get the ball will be addressed this offseason, but there were plenty of opportunities for both teams to avoid overtime in the first place. The Chiefs just happened to be on the winning end this time around.