He's smaller and not even explosive. The Canelo that fought Matthew Hatton is the one fighting now and unless he juices up fast he will get knocked out.
Anyone can provide pictures or videos? I doubt he is any smaller. He and GGG will both weigh in at 160 pounds or within a few ounces of 160 pounds. They will both weigh 171 pounds in the ring give or take a pound or two. They will both have been tested often and will be clean. It will be a fair fight but the judging might again not be fair. Do an internet search. There are lots of pictures and film of Canelo in training for this fight..