If by some miracle Cotto beats Canelo, he would rather throw the belt in the trash can than fight GGG.
However the ABC's are corrupt as **** so they will probably give him more optional defenses and ignore the GGG mandatory.
The only sure things are the fights that are signed. I think Canelo will fight the winner of Lemieux-GGG at 160 pounds if he beats Cotto. If Cotto wins I doubt he will fight the winner.
What everyone is assuming and hoping...
Cotto ain't fighting ggg, even if he beats Canelo
Canelo would probably fight GGG sometime in 2016 but I think canelo milks a title defense or 2 before then..