The San Francisco 49ers shockingly announced that star forward Christian McCaffrey will sit out of the team’s opener against the New York Jets on Monday night.

What was shocking to everyone, didn’t seem to be to his replacement, Jordan Mason, who reportedly revealed that the team had violated an NFL rule after the 32-19 victory on “Monday Night Football.”

Mason, who had a stellar game in his first-ever start for the 49ers, spoke to ESPN’s Lisa Salters after he totaled 147 rushing yards with a touchdown on 28 carries in the win. He said he knew Friday he would start in place of the injured McCaffrey.

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San Francisco 49ers running back Jordan Mason reacts after a run against New York Jets safety Chuck Clark during the fourth quarter at Levi’s Stadium. (Darren Yamashita-Imagn Images)

“When did I hear? Maybe Friday. Friday night, something like that,” Mason replied when Salters asked when he heard he would be starting.

Mason also had a post-game interview, where he appeared frustrated when another reporter asked him again when he would start.

“That question is exactly why I’m angry,” he said. “That’s why I don’t like to talk to the media, because you say one thing right and then, you know, I don’t know. Just skip that question.”

Head coach Kyle Shanahan said after the game that Mason didn’t know he would start, but was told he would play a lot, according to NFL Network.

“He wasn’t sure if he was going to start until today,” Shanahan said.

McCaffrey has been struggling with a calf/Achilles injury in recent weeks, but he expressed confidence that he would be able to face the Jets. That was not the case just over an hour before kickoff, when the 49ers were forced to waive their inactive players.

49ERS BEAT JETS AS JORDAN MASON TAKES PLACE FOR INJURED CHRISTIAN MCCAFFREY

McCaffrey was listed as questionable prior to the game and the 49ers had not said anything about his availability until the inactive players were released.

So if Mason’s words are true and he found out on Friday that McCaffrey was unavailable to play and he would start, then the 49ers violated an NFL rule by marking him as questionable with a chance to play, even though that is not the case.

Christian McCaffrey, #23 of the San Francisco 49ers, runs with the ball for a touchdown during 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, all NFL teams want the right injury report to prepare for their opponents. However, with fantasy football and now legalized sports betting playing a major role in the NFL, injury reports are of utmost importance for creating lineups and betting on the right players.

“The information must be credible, accurate, timely and specific within the guidelines of the policy, which is of the utmost importance to maintaining the integrity of the game,” the league’s policy on injury reporting reads, via Pro Football Network.

What happens if the league investigates the situation and finds that the 49ers falsely reported McCaffrey? It will likely be a fine, but if the violation is serious enough, the NFL could consider suspending players and forfeiting draft picks.

One of the most notable examples of this came in 2019, when Pittsburgh Steelers quarterback Ben Roethlisberger did not report to a practice report. It was said that rest was the reason Roethlisberger did not practice on Wednesday, but he left the game with a non-contact elbow injury that ultimately required season-ending surgery. He practiced on Thursday and Friday that week but was not listed on the final injury report.

Running back Jordan Mason, #24, of the San Francisco 49ers carries the ball against linebacker Quincy Williams of the New York Jets 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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