Having suffered 16 wounds, she later underwent three hours of surgery to repair lacerations to her front temple, shoulder and arm.
McGrath was questioned at the scene by police, who took both him and the dog back to his partner's house.
The following day officers checked to see if he had handed over the animal to be humanely destroyed, but McGrath told them he had killed the dog himself.
Oh, really? Why?
The court heard he had received death threats and was under pressure to dispose of the dog, but did not have the money to take the animal to a vet to be euthanised.
Well, maybe the police should have seized it and ensured it was destroyed then?
I mean, really, the honour system for a dangerous dog? What are they putting in the Guinness over there?
No remains of the dog were found when police searched McGrath's home, but during interviews he claimed to (sic) killed the animal at a dump near Ligoniel.
"He admitted killing the dog by hitting it over the crown of the head with a hammer twice, and then putting its remains in a wheelie bin, covering it with copper wire and petrol, and setting the remains and the tools he used on fire," a prosecution barrister said.
But no evidence of dog remains or the burnt bins were found during further searches of the dump area either.
The judge said it was a "terrible case" in which a girl had sustained "lasting injury" and a dog was treated in an "appalling" manner.
He sentencing McGrath to four months in prison but that term is now subject to appeal.
I wonder where the animal is now? It's not over the Rainbow Bridge, is it?