The NFL’s habit of disclosing weekly fines can often reveal the league office’s opinion regarding whether the game officials failed to call a foul when a flag should have been thrown.

It happens most frequently regarding the rule against lowering the helmet to make forcible contact with an opponent. On Monday night, for example, a clear instance of lowering the helmet and initiating by Bills running back James Cook drew a $21,167 fine; the violation was not flagged.

During Sunday’s game between the 49ers and the Seahawks, a more consequential miss happened — and the league’s decision to impose a fine acknowledges it.

With 1:13 to play and the Seahawks facing first and 10 from the 50, Seattle quarterback Sam Darnold threw a pass to receiver Jaxon Smith-Njiba. The reception was broken up by what Fox’s Kevin Burkhardt called a “wicked hit” from 49ers safety Malik Mustapha.

The hit was also illegal, in the eyes of the league office. Mustapha was fined $6,998 for the blow that left Smith-Njigba rattled after the play. (Mustapha apparently responded to the fine by posting a one-word message — “soft” — on social media.)

But no flag was thrown for an illegal hit on a defenseless player. If the officials had seen the play the way the league office did, the Seahawks would have gotten a first down at the San Francisco 35 with 1:09 to play.

Instead, the Seahawks failed to convert, thanks both to an uncharacteristic drop from Smith-Njigba and a razor-thin decision that receiver Cooper Kupp had failed to get the ball to the sticks before it went out of bounds.

We’ll never know what the Seahawks would have down with a fresh set of downs from the 35 in a three-point game with 69 seconds left. But we do know, based on the fine imposed on Mustapha, that the league office believes the hit was illegal and, by implication, a flag should have been thrown.