The remaining two flags came on one kickoff return. We counted 24 possible flags on defensive players compared to 13 for offensive players.

Defenders were twice as likely to commit these penalties.

Six of those plays included at least one obvious penalty.

On 43 passes, we saw just 10 plays including at least one questionable hit.

On those 13 plays, we saw 26 possible penalties, 15 of which were deemed 'obvious' penalties.

Of the 24 runs in the first half, 13 plays included a questionable hit.

Running plays were far more likely to include a possible penalty.

Based on the language above, 22 of those possible penalties were obvious calls, leaving 17 borderline calls.

Over the course of 75 first-half plays, we found 39 possible penalties on 24 plays.

We've embedded the spreadsheet below, as well.) We've included a video clip of every play that includes a possible penalty.

So how will this affect the game? To get a sense, we reviewed the first-half of the Week 13 Steelers-Bengals game on Monday Night Football and tried to identify as many of these now-illegal hits as we could. 'Lowering the head to initiate contact with the helmet is a foul.' Right now, this is all we have from the league: While the rule has been passed, the league still has to formulate the official language and set a standard for what will be considered a flaggable hit. League owners unanimously passed a rule that outlaws lowering the helmet and using it to initiate contact with an opponent.

If you're a fan of college football's targeting rule, I've got good news: The NFL is getting its very own version of it, starting next season.

Penalties in the first half of mnf game