difference between cut block and chop block

[MJT]

Originally posted by Smiley
Actually, the initial block does not have to be above the waist, it can be below the waist. But, you're right, the second block must be delayed and at or below the knees to be a chop block. Had one last night.

Only in NF must the 2nd block be delayed and at or below the knees. In NF simultaneous blocks are legal. 2-3-9

In NCAA, it can be a high-low, low-high, or low-low combination and in some cases simultaneous blocks in the above mentioned are fouls, and in some cases they are legal blocks. See AR 2-3-3 for situations.

In NFL, a chop block can also be a low-high blocking combination. Also in the NFL it can be a chop block if only one block occurs. This example is "on a forward pass play, A1 chops a defensive player while A2 confronts the defensive player in a pass-blocking posture but has not physically engaged with the defensive player (a "lure"). (12-2-14c) There are 10 such examples given after the chop block definition in 12-2-14.