For reference, just a couple of examples of Mack's play :
Mack goes head-to-head with TE Virgil Green, sets him, and then sheds him.
This isn't really fair, but it's fun to watch. Mack v WR #11 Jordan Norwood. Norwood is listed at 5'11", 180. Mack is 6'3" and around 280 lbs (reportedly put on 20-25 lbs from his rookie year 255 lb playing weight). It goes as you would expect.
Obviously this play was not designed for Norwood to block Mack, but Mack either read the play or had an outside assignment that had him get up into the backfield and cutoff Norwood before he could get to the corner or safety. Notice also that he explodes outside and avoid the pulling RT #79.
The TE/HBack #47 Kellen Davis motions to Mack's side and prepares for Mack's power. When he lowers his head, Mack shows his excellent mobility and footwork and gives the Ole, gets into the backfield free and clear and makes the TFL.
Notice that the FB #40 leads to the inside of #47. This means that Kellen Davis wanted to get inside leverage on Mack and kick him out. So he gets good position, but gets defeated so quickly that Chris Ivory doesn't have a chance to make something happen.
What doesn't show up on the stat sheet is how Mack's presence presents opportunities for his teammates. In this case, the NYJ have 2 OL assigned to block Mack, including the Center who totally ignores DL Denico Autry. Autry beats the RG inside and runs untouched into the backfield and makes the nice TFL.
Note also, it looks like the RG expected help from the Center against Autry.
Stalemates pulling R Jonathan Cooper and forces the play to the outside
https://gfycat.com/ObedientNaturalCentipede
Forced fumble :
v TE :