NFL owners voted for seven rules changes on Tuesday as part of their annual meetings, and probably the highest-profile change was the total banishment of chop blocks. This news was met with a lot of confusion. Many fans had believed that chop blocks were already illegal -- and most already were -- while others incorrectly believed that cut blocks, a staple of many blocking schemes, were now outlawed.

First of all, if your team runs a zone-blocking scheme, there's no immediate reason to start panicking. Just to make it clear, cut blocks in one-on-one blocking situations remain legal, but the rule change that eliminates chop blocks will certainly have an effect on line play going forward. Furthermore, the change will likely create a little more ambiguity for referees, and that gray area could be something to watch this upcoming season.

So let's lay it all out.

Some chop blocks were already illegal

The main distinction between cut blocks and illegal chop blocks is that in most cases, players were not allowed to cut block a player who is already engaged with a teammate. This is what's called a "high-low" block, and apart from a few specific situations, it has already been illegal.

Check out the Dolphins left tackle in the play below. He's engaged with Jets defensive end Leonard Williams as tight end Jordan Cameron slices across the formation and chops him down from his feet. This has been, and will continue to be, illegal.

On the play below -- a pass play -- Rams left tackle Greg Robinson gets called for a chop block because when he takes out No. 97 Caraun Reid, Reid is already engaged with the left guard.

However, if this had been a run play, it may not have been flagged. Here's why.

This type of chop block was legal last year, but is now illegal

There were still a few instances last year in the NFL where it was legal to chop block a player who was already engaged with a fellow offensive lineman.

As it was written in the 2015 rulebook:

A Chop Block is a block by the offense in which one offensive player (designated as A1 for purposes of this rule) blocks a defensive player in the area of the thigh or lower while another offensive player (A2) engages that same defensive player above the waist. A Chop Block is a legal block in the following situations on Running Plays: -- Offensive players A1 and A2, who are initially aligned adjacent to each other on the line of scrimmage, may chop a defensive player. -- Offensive players A1 and A2, who are initially aligned more than one position away from each other on the line of scrimmage, may chop a defensive player when the flow of the play is toward the block.

This play below, as laid out by Brandon Thorn on Twitter, shows you a formerly legal version of the chop block.

Tricks of the trade for DL vs the run especially vs Combo blocks. Holding the OL, preventing him from releasing. pic.twitter.com/PSSXTtjleQ — Brandon Thorn (@VeteranScout) March 17, 2016

As Thorn points out, defensive linemen who are facing double teams from offensive linemen may sometimes try to hold on to the first lineman in hopes of keeping him from getting into the second level to block linebackers. Last year, the second of the two adjacent linemen could chop down that defensive lineman if he was holding on a little too long. This means the defensive lineman has to keep his head on a swivel.

Former Giants tackle Geoff Schwartz reacted to the news with frustration.

The best way to get a DT to not hold us on double teams, is a chop block. Now there's nothing to stop them. Fun times. — Geoff Schwartz (@geoffschwartz) March 22, 2016

While defenders are certainly happy about the rule change, many offensive linemen will have to alter the way they play, particularly on those combo blocks.

These type of cut blocks are still legal

That said, of course, one-on-one cut blocks going in the direction or flow of the play are still legal, and will still feature prominently in many NFL offenses. Zone blocking schemes -- featured in Seattle, Houston, Denver and several others -- use cut blocks as a part of their strategy, typically on the backside of plays to try to take away pursuit, away from the ball. Offensive linemen will dive at defensive players' legs to knock them to the ground, and this is still legal as long as it's going in the same direction of the play.

Take left guard Justin Britt in the example below. This is still legal because it's clearly one-on-one and the nose tackle is not being engaged by another offensive lineman.

In the very next play below, the two cut blocks with the right guard and right tackle are also still legal. This is a method of pass protection meant to clear passing lanes on quick throws.

So, cut blocks remain. But, the elimination of those combo chop blocks means, as usual with NFL rules, that there will be some gray area.

There's a gray area

Oh joy, more ambiguity and "judgment calls" in football!

With the announcement that the double-team chop blocks are now illegal going forward, several former and current players reacted on Twitter.

Rule change on #ChopBlock will be hard to enforce. Judgement call by ref, am I ENGAGED or AVOIDING the DL? #GoodLuck — Shaun O'Hara (@ShaunOHara60) March 22, 2016

As O'Hara points out, it's not always crystal clear what's going through an offensive lineman's head when he's blocking, and being "engaged" can be a little vague. Packers lineman T.J. Lang agreed.

100%.. Hard to avoid that 3 tech when he is grabbing and trying to prevent his LB from getting blocked. https://t.co/v8xQ3jz24k — TJ Lang (@TJLang70) March 22, 2016





Take these examples from Duke Manyweather of where the gray area might show up.

You can see the center quickly punch with his right hand before moving downfield, and the defender is quickly cut down by the right guard immediately after. Is this going to be considered illegal? Was the center "engaged" with that defensive lineman?

Here's another example. The same question could be posed: Does the center disengage from his block before the left guard throws his chop?

We're probably going to be arguing about this exact type of thing next year.

The elimination of the chop block is about player safety, so offensive linemen are just going to have to adjust. If you were initially freaked out thinking that the cut block had been completely eliminated from the game, fear not. Your favorite zone-blocking team will still be able to throw cuts on the backsides of plays, and ultimately, the banishment of the chop block isn't likely to create a sea change in how teams block or how they run the football.

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