The New England Patriots were flagged for a pair of fourth quarter defensive holding calls against defensive tackles Alan Branch and Malcom Brown. Now holding calls on their own aren’t a rare occurrence, but having them go against the defensive linemen is not something you see very often.

The normal lack of holding calls against defensive linemen actually stem back to the Patriots, too.

In 2010, the NFL decided to move the Umpire from the defensive side of the ball and into the offensive backfield. The Umpire’s job is to see if there are any penalties in the trenches. Certain offenses (read: Patriots, Wes Welker) utilized these officials in pick plays to generate separation for the receivers and this lead to the Umpire being in the middle of a lot of contact in traffic. So with the official’s safety in mind, the NFL moved them out of harm’s way.

As SB Nation’s Geoff Schwartz noted last season, a side effect of this move led to a great reduction in defensive holding calls because there was no longer an official with a strong vantage point of the defensive side of the trenches.

Defensive linemen were flagged for 27 defensive holding calls in 2009, the year before the Umpire changed location, to an average of 11 per season from 2010-15. There was an uptick in the call in 2016 (19 flags) and we’re already at 17 defensive line holding calls through 6 weeks of the 2017 season, which puts the pace at a whopping 48 projected penalties.

With the Umpire behind the offensive line, the defensive lineman will have to commit a very obvious penalty to be called- except that now the back judges are throwing flags for defensive holding, according to Patriots head coach Bill Belichick.

“It’s called by the back judge,” Belichick explained on Monday. “A lot of times, on those combination blocks, one guy is leaving the block, the other guy is trying to take over the block and the defender is playing the guy that’s leaving him. Sometimes he gets too much of him in the official’s eyes”

This change in responsibility makes sense, too, since the back judge has a better line of vision for the defensive tackles- and someone has to watch the defensive trench.

Here are the two plays where the Patriots were flagged:

Alan Branch (#97, nose tackle)

The Jets are trying to have their left guard slide in front of Branch so their center can block Kyle Van Noy at the second level. Branch has other ideas and engages with the center, spinning him around.

Now the rule book states that defenders can push or pull offensive players if they are obstructing their path to the ballcarrier, but the language reinforces that if the offensive player is trying to get out of the defender’s way, then it should be a penalty. Since the center is trying to get around Branch and not engage him, the officials viewed that as a penalty on Branch.

Malcom Brown (#90, nose tackle)

This is nearly the same exact combination of blocks from the center and left guard. Brown grabs the center, who is trying to get to Van Noy in the second level, and spins him around. That said, the center clearly engages with Brown.

I feel like these defensive holding calls in the trenches are called like offensive pass interference. The defender will get called if he has a full arm extension to engage a blocker outside of his body and it’s up to the back judge to determine the intent of the offensive lineman to either engage or avoid the defender.

The Patriots defensive tackles have to try and be more prepared against combination blocks because the trick is knowing when the offensive blocker is disengaged and letting go when they exit your frame. While it seems that the officials previously gave the benefit of the doubt to the defensive linemen, defensive holding is being called at a higher rate than ever before.