Trent Williams, a player for the Washington Commanders, was accused of throwing a punch at Nick Bosa from the San Francisco 49ers during a game on October 11, 2020.

At first, Bosa got in trouble for rough play, but the NFL changed their decision and fined Williams $13,269 for the punch. 

Williams said he was just trying to protect himself after Bosa pushed him down. 

Even though the referees on the field didn't see Williams throw the punch, the league's replay officials checked the video and said he broke the NFL's rule against rough play.  

The NFL's rule on rough play says, "No player shall strike, kick, or knee an opponent."

Williams tried to fight the fine, but the NFL said it was right. 

People have argued a lot about whether or not Williams really threw the punch. Some say the NFL made the right call, others think it was unfair to Williams. 

This whole thing also brought up questions about the NFL's replay system. Some think it's not good and shouldn't be used to change on-field calls. Others say it's really important for making sure the game is fair. 

The debate about whether Williams threw the punch is likely to go on for a while. It's a complicated issue with no easy answers.