Video: Jordan Mason 'Mad' When Questioned About 49ers' RB1 Timeline amid CMC Injury

Jordan Mason's big night in a 32-19 win over the New York Jets is quickly being overshadowed by the timing of when the San Francisco 49ers running back knew he was going to start.

Mason told ESPN's Lisa Salters he was aware "maybe Friday night" that he'd be deputized to fill in for an injured Christian McCaffrey. McCaffrey was listed as questionable and only ruled out Monday, so Mason's comment raised some questions.

The third-year back was again asked in his postgame press conference when he was made aware he'd start. He responded by saying, "That question right there is why I'm mad," and declined to answer.

The NFL is very particular when it comes to teams reporting injuries. If the 49ers knew on Friday they'd be without McCaffrey in Week 1, they couldn't keep that information hidden until game day.

The league fined the Atlanta Falcons and their head coach last year when they weren't entirely forthright about the status of running back Bijan Robinson.

Not surprisingly, San Francisco head coach Kyle Shanahan refuted Mason's original account of events.

"I never told Jordan he was going to start," he told reporters. "I told him he had to be ready a bunch, but that might've been [running backs coach] Bobby [Turner] or somebody trying to pump him up. But I knew he was going to have to play a lot and I told him that he was going to have to, wasn't going to be like usual, he was going to be a number two back, that was splitting a lot of the time. But no, he didn't know he for sure was doing that until today."

It's plausible Mason simply misspoke. He was riding a high after a breakout performance and didn't consider how his comments would be taken at face value and scrutinized so thoroughly.

McCaffrey was limited in practice all week, so approaching the backup to say he might be starting was something any head coach would do. That doesn't mean Shanahan was resigned to not having the two-time All-Pro.

The league office might be following up with the Niners in the coming days just to make sure.