Christian McCaffrey may have missed Week 1 game due to a potential NFL rule violation, according to Jordan Mason.

The 49ers stunned fans by announcing that Christian McCaffrey would not be playing in their first game against the Jets on Monday night.

Jordan Mason, the backup, did not seem shocked by the team's alleged violation of an NFL rule following its 32-19 win on "Monday Night Football."

Mason, who had a standout performance in his first start for the 49ers, shared with ESPN's Lisa Salters that he knew on Friday he would be starting in place of the injured McCaffrey.

Mason replied, "Maybe Friday. Friday night, something like that," when Salters inquired about when he discovered he was beginning.

Another reporter asked Mason about starting, causing him frustration during a postgame interview.

"That question is why I'm mad," he said. "I don't like talking to media because when you say one thing, you don't know what to say next. Just skip that question."

Mason was informed that he would play a significant role in the game, but he was not aware that he was the starting quarterback, according to head coach Kyle Shanahan.

Shanahan stated that he was not certain about starting until today.

McCaffrey had been dealing with a calf/Achilles injury for the past couple weeks, but he expressed confidence that he would be able to go against the Jets. However, just over an hour before kickoff, the 49ers had to submit their inactives.

Before the game, McCaffrey was listed as questionable, and the 49ers remained silent about his availability until the inactives were released.

If Mason's statement is accurate, and he learned on Friday that McCaffrey was unable to play, he would be starting, then the 49ers would have violated an NFL rule by classifying him as questionable with a possibility of playing, even though that was not the case.

While injury reports are crucial for NFL teams to prepare for their opponents, they are also essential for fantasy football and sports betting enthusiasts to make informed decisions about their lineups and bets.

The league's injury report policy, as stated via Pro Football Network, emphasizes the importance of credible, accurate, timely, and specific information that adheres to the policy guidelines, in maintaining the integrity of the game.

If the league investigates the situation and determines that the 49ers improperly reported McCaffrey, it is likely that they will face a fine. However, if the offense is severe, the NFL may consider suspending players and forfeiting draft picks.

In 2019, the Pittsburgh Steelers failed to report quarterback Ben Roethlisberger on a practice report, citing rest as the reason for his absence on a Wednesday. However, he suffered a non-contact elbow injury during the game and underwent season-ending surgery. Despite practicing on Thursday and Friday, Roethlisberger was not included on the final injury report.

The league will likely react to Mason's remarks.

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