The Baltimore Ravens were called for three illegal formation penalties on their opening drive against the Kansas City Chiefs thanks to an emphasis on where offensive linemen line up — ironically, because of the Chiefs.

Ravens left tackle Ronnie Stanley was flagged four times for the same infraction in the first half. According to the NFL rulebook, seven players must be on the line of scrimmage before the snap — almost always a combination of five offensive linemen, plus two receivers, running backs or tight ends.

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For offensive tackles, that typically means they have to have their helmet at the waist of the center before the snap to be considered at the line. This allows them to remain effectively a step or two behind the line in anticipation of a pass rush. Stanley, like many offensive tackles do, was taking an extra step back to give himself an advantage against opposing pass rushers.

You may remember this being a storyline from last year’s season opener, when it was Chiefs starting right tackle Jawaan Taylor who was criticized for lining up illegally — but the referees weren’t flagging him consistently.

“To be on the line of scrimmage, his helmet has to break the waist line of the center. And to be honest, we’ve watched him the whole game, he’s really not remotely close,” NBC rules analyst Terry McAulay said during last year’s opener. “And it’s really putting the defender at a tremendous disadvantage when he can be that far back.”

The NFL has made it a point of emphasis for officials this year to flag offensive tackles who try to create extra breathing room at the line of scrimmage.

And the Chiefs ended up being the first beneficiary.