Nearly every NFL game includes one or more injuries to players. Thursday night's game saw referee Adrian Hill suffer a non-contact leg injury that ended his night.

And then everyone saw that the league has no viable backup plan for the unexpected departure of the chief of the officiating crew.

Oh, they have a plan. It's not just viable. Umpire Roy Ellison was given the white hat and, eventually, a microphone. Ellison became both the umpire and the referee for the rest of the game.

Two important jobs in one, for a game with plenty of playoff implications. And with two eyes instead of four watching the action behind the line of scrimmage, Ellison missed an obvious illegal touching violation in the fourth quarter, when a desperation throw by a harassed Josh Allen clearly struck one of his lineman.

There may have been other issues far less obvious in real time. Holding fouls may have been missed. Illegal hands to the face, too. Hits to Allen that may have been roughing the passer, which falls squarely within the referee's purview and not the umpire's, may not have been spotted.

In the postseason, the NFL assigns five alternate officials to the wild-card round and divisional games. For the conference championships and Super Bowl, the eight-person crew has eight on-site alternates. For 272 regular-season games, an injury results in the crew shrinking by a member — and by someone else taking on the assignments of two officials.

At a time when the NFL absolutely should be implementing full-time officials, the absence of any alternates at regular-season games is jarring. With the proliferation of gambling, from which the NFL handsomely profits, some of the millions the league is making should be directed to having extra officials on site for every game that counts.

Ideally, each member of the crew would have an understudy. At a minimum, there should be one extra official who can step in if/when an injury happens.

It's amazing it doesn't happen more often. Artificial turf is unforgiving. The middle-aged-and-older officials are exerting themselves to keep up with the action. (And, at times, to scamper away from a trampling.) A torn Achilles tendon (which seems to be what happened to Hill) happens all the time to aging bodies — even when not trying to accelerate on cement covered by plastic grass.

Don't expect the NFL to change anything, for one very important reason. The league views the entire officiating function as a cost that need not become more costly. In 2012, for example, the Commissioner justified a lockout of the officials by insisting that replacements would be just as effective. (Spoiler: They were not.)

But there's no way to force the NFL to do it. No one is going to boycott NFL games because officials are part-time employees, or because there's no extra official to step in when one of the officials is injured. Short of Congress insisting on a significant increase in the officiating budget as part of a broader look at the NFL's safeguards for protecting the integrity of legal wagers, it will never happen.

Even if it should have happened years ago.