User blog comment:AYET/Who will come?/@comment-6920514-20130625135432/@comment-6122161-20130625191652

I have to disagree there man because I think Luffy still holds resentment towards Garp for all the harsh training and the beatings he put him through as a kid. However, that's why I said "initially." I think Luffy would at first not care but, after his crew knocks some sense into him, he would go all out to save his grandpa just like he did Ace. And besides, Luffy didn't hesitate with Ace because they were really close and he always spoke very fondly of him. However, I don't recall Luffy speaking fondly of Garp.

As for Sengoku, he left the Marines so it wouldn't be his duty anymore. Also, he left right after Garp did, so this could imply that he's somewhat loyal to him. And anyways, I'm pretty sure Garp, Sengoku and Kuzan could take on the Marines.