I do powerlifter at a decent level. Tendons are what determines the amount of effort i'm allowed to train at a given volume and frequency.
When not using aromatising steroids, tendons get bigger and stronger as the muscle gets stronger and bigger. NFL players are quite bulked, so they got strong tendons. Less likely to get injured aswel cause it takes more force to tear into them, and they are more resistant. They can make a better recovery because the bigger tendon grows back togheter at the same pace a small tendon will, when operated correctly. Because of this, they'll be quicker at certain tendon strenghts and can begin revalidation quicker, and their revalidation will be faster.
Football players cannot bulk up, like the low weight (-63 etc) lifters,their tendons are much more initiated in everything they do, whilst beeing smaller cause less muscle around, when they get a brutal challenge, the amount of force required to break it, is alot smaller.
HOWEVER
Marchisio isnt a pace depending player, he's a stamina player with a decent speed. We arent talking about Ronaldo, Bale, Cuadrado,.. A CDM/CM doesnt need pace and agility to be on top of his game, he needs stamina. Marchisio can come back from this and gain a little weight, which is usually what they recommend to players who had this
-Both Del Piero and ROnaldo stopped having ligament tears once they put on extra mass. They werent as good as before cause their game needed the pace and agility.
SO yeah, Marchisio will be out for approximately 4-6 months if its the ACL. But he'll come back to his previous form.
Be happy it wasent dybala.