If Pacquiao beats Marquez a third time should there be a 4th fight?

No, if Pacquiao beats him again, however closely the fight may be, there shouldn't be a fourth fight.

I think if any of them 2 win by wide decisions or either fighter wins by ko they shouldnt have to and will be the real winner of the 3 fights. But if marquez wins barely they should make a 4. Thats would mean jmm won 4 fights vs manny

If it happens again, then that's it. It's clear Marquez won't win unless he stops getting knocked down.

it'll become silly, i think but i believe 3rd fight will be a war

No, thats too many chances. If JMM wins then yes. What if someone tied Marquez' shoes together between rounds???

No, thats too many chances. If JMM wins then yes.