Try not to fall into the classic American mistake of confusing size for toughness lid.
All these supposed super human gridiron monsters are just fat on water retention in their puny muscles. I'd guarantee they'd be pleading for a substitution after the first Ruck in rugby, never mind when the opposition prop tests out their pain tolerance early doors by giving them a slap.
The game isnt being stopped after five seconds so they would be blowing out of their arises if they did make it to 20 minutes in thick mud that's a great leveller.
Each and every American footballer is an utter fraud. A big phoney shithouse like all the wrestlers.
I'd pay good money to see an average rugby team hurt their best.