▁by ▁the ▁defense ▁awards ▁them ▁enough ▁yard age ▁to ▁att ain ▁it . ▁▁ ▁R ules ▁are ▁asym met rical ▁in ▁regard ▁to ▁whether ▁a ▁team ▁can ▁score ▁directly ▁as ▁a ▁result ▁of ▁a ▁penalty . ▁The ▁off ensive ▁team ▁cannot ▁do ▁so ; ▁if ▁a ▁f oul ▁that ▁is ▁pen al ized ▁from ▁the ▁spot ▁of ▁the ▁f oul ▁is ▁called ▁on ▁the ▁defense ▁in ▁its ▁own ▁end ▁zone , ▁the ▁ball ▁is ▁placed ▁on ▁either ▁the ▁one - yard ▁line ▁or ▁the ▁two - yard ▁line , ▁and ▁the ▁off ense ▁must ▁try ▁to ▁score ▁from ▁there . ▁However , ▁pen alt ies ▁called ▁on ▁the ▁off ense ▁in ▁its ▁own ▁end ▁zone ▁can ▁result ▁in ▁the ▁defense ▁scoring ▁a ▁two - point ▁safety . ▁ ▁If ▁the ▁defense ▁commits ▁a ▁f oul ▁during ▁the ▁last ▁play ▁of ▁any ▁quarter , ▁the ▁off ense ▁usually ▁has ▁the ▁option ▁to ▁accept ▁the ▁penalty ▁and ▁re play ▁the ▁down ▁even ▁with ▁the ▁clock ▁showing ▁ 0 0 : 0 0 ▁( i . e ., ▁an ▁un tim ed ▁play ). ▁Con vers ely , ▁in ▁most ▁cases ▁where ▁the ▁off ense ▁commits ▁a ▁f oul ▁during ▁the ▁last ▁play ▁in ▁the ▁half , ▁the ▁play ▁in ▁which ▁the ▁f oul ▁is ▁committed ▁is ▁usually ▁null ified ▁and ▁the ▁half ▁ends . ▁ ▁In ▁American ▁football , ▁when ▁multiple ▁fou ls ▁occur , ▁when ▁both ▁teams ▁commit ▁a ▁f oul ▁during ▁a ▁play , ▁regardless ▁of ▁sever ity , ▁the ▁fou ls ▁are