What's the best way to repair the broken corner of a door?

It's the lower corner on the doorknob edge. It was previously repaired with bondo, but that has since crumbled away leaving a hole, so I don't want to go that route again. I was hoping to find some kind of sleeve, like a door guard only triangular, that I could just slide over the corner and screw into the door and be done with it, but I have yet to find anything like this. I'm sure I've seen something like that but perhaps not knowing what it's called is hampering my search. At the moment I've attached a corner brace, which is doing the trick, but it's a little thick and sticks out from the door. I've thought about just grinding out a thin, triangular section from the inside face and edge of the door so the brace will sit flush, but ultimately I'd like to find something thinner and more aesthetically pleasing. I'm renting and the owner does not want to spring for a new door (it was he who did the earlier repair with bondo). Any suggestions would be greatly appreciated.