I thought Marty's comments yesterday regarding Homer yesterday were spot on.
I'm paraphrasing here: "Anytime something goes wrong with this man, he simply cannot put it away because it always seems to stick with him."
Examples:
After Janish's error, Homer gives up a 3 run HR.
After Votto doesn't pick up a pop up causing Adam Jones to get a 'single,' Guererro singles and Derek Lee hits a 3run HR.
Of course, these are just his last two starts since coming off the DL, but doesn't it seem like it's happened a lot before?