The San Francisco 49ers shockingly revealed that star running back Christian McCaffrey will not play in the team's season opener against the New York Jets on Monday night.
But what was a shock to everyone else likely wasn't to his backup, Jordan Mason, who may have revealed he violated NFL rules after his team's 32-19 win on “Monday Night Football.”
Mason, who had the best night of his career in his first start for the 49ers, rushing 28 times for 147 yards and a touchdown in the win, said in a conversation with ESPN's Lisa Salters that he knew he would start in place of the injured McCaffrey on Friday.
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San Francisco 49ers running back Jordan Mason reacts after a run on New York Jets safety Chuck Clark during the fourth quarter at Levi's Stadium. (Darren Yamashita – Imagn Images)
“When did I find out? Probably Friday. Friday night, something like that,” Mason said when Salters asked him when he found out he'd be starting.
Mason also took part in a post-game interview, but appeared annoyed when another reporter, who had learned he had started the game, asked him another question.
“That question is what makes me angry,” he said, “and that's why I don't really like talking to the media, because I can say one thing right and then, you know, I don't know. Skip that question.”
According to NFL Network, head coach Kyle Shanahan said after the game that Mason didn't know he would be starting, but rather had been told to play a lot.
“He wasn't sure until today if he was going to start,” Shanahan said.
McCaffrey had been plagued by calf and Achilles injuries in recent weeks but seemed confident he would be able to play against the Jets, but that confidence evaporated when the 49ers had to turn in a suspended player just over an hour before kickoff.
49ers beat Jets with Jordan Mason replacing injured Christian McCaffrey
McCaffrey had been questionable before the game, and the 49ers were quiet about his availability before the suspended players were announced.
So if Mason's words are true and he ends up starting on Friday after learning McCaffrey would be unavailable, the 49ers would have violated NFL rules by listing McCaffrey as questionable when he is unlikely to play.

Christian McCaffrey, wearing No. 23 of the San Francisco 49ers, runs the ball for a touchdown in the second quarter against the Kansas City Chiefs during Super Bowl LVIII at Allegiant Stadium on February 11, 2024 in Las Vegas. (Steph Chambers/Getty Images)
Of course, every team in the NFL wants a proper injury report to prepare for their opponents, but with fantasy football and now-legal sports betting playing a major role in the NFL, injury reports are paramount for setting lineups and placing bets on the right players.
According to Pro Football Network, the league's injury reporting policy states that “information must be reliable, accurate, timely and specific within the guidelines of the policy, which is paramount to maintaining the integrity of the game.”
If the league investigates the situation and finds that the 49ers improperly reported McCaffrey, what will happen? Fines will likely be levied, but if the violation is severe enough, the NFL could suspend a player or strip a team of draft picks.
One of the most notable examples is when the Pittsburgh Steelers did not report quarterback Ben Roethlisberger to their practice report in 2019. It was said that Roethlisberger's failure to practice on Wednesday was due to rest, but he left the game with a non-contact elbow injury that ultimately required season-ending surgery. He practiced Thursday and Friday that week but was not listed on the final injury report.

San Francisco 49ers running back Jordan Mason (No. 24) carries the ball against New York Jets linebacker Quincy Williams during the fourth quarter at Levi's Stadium. (Darren Yamashita – Imagn Images)
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It will be interesting to see how the league responds to Mason's comments.
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