Continuity mistake: Nino gets trussed up in silver duct tape. The boy gets bundled over the shoulders of one of the bad guys, and you can see that there is only a small amount of tape around his legs. They go straight inside the meat packing factory and suddenly in the next shot, there is a huge amount of tape around the boy's legs.
Continuity mistake: Rex catches the baseball cleanly in his teeth without damaging it. There is then a shot of the dog with a very damaged ball in its mouth, then a few seconds later, another shot and the ball is different again.
Continuity mistake: Nino is hanging from a meat hook and moves along the 'I' beam. There's a close up shot of the rusty roller that supports the meat hook. Just before it falls off, there is another close up shot and it is a different roller.
Revealing mistake: Rex the dog leaps through the protective wire netting around the baseball practice area. As he jumps through, you can see the netting split apart and that the edges of the 'broken' wire mesh are protected with some duct tape.
Continuity mistake: As Rex runs towards the wire netting to save Nino, the boy has his baseball glove on. He puts his hands up to protect his face, and the glove has gone.