The "countless death matches" is a wrong translation
Roger: Regrettably, they will find the girl and kill her but Garp, the child that will be born bears no sin.
Roger: You and I have fought to the death 10s of times already haven't we!!?
Roger: If it's you Garp, I can trust you like I'd trust my comrades!!
Roger: Protect the child!!
Garp: Don't say something so selfish!!!
Roger: No, I'm sure you will protect the child for me......!!
Roger: I'm leaving my child in your care!!