When people approached the pit bull, who was there with another dog, a woman with Vinten said she could pet him, but it was also said that the dog, described as “rowdy and excitable”, did not didn’t like females.

Vinten was arrested at the scene and the victim was taken to Alder Hey Hospital where she required plastic surgery and was left with scarring on her left cheek.

A photo shown to the judge showed the larger scar was still visible but had faded.

A doctor said there was a risk of lip deformity due to muscle and nerve damage, but it was not yet known whether this would be permanent.

The court heard the victim, now aged four, had no further hospital appointments and her mother said “they just wanted to get on with their lives”.

Frank Dillon, defending, said Vinten had been living in a bail facility for days before the attack and had never kept a dog before.

He said Vinten, who suffered from mental health problems, should have introduced the dog in stages in public.

He told the court the accused was remorseful and had pleaded guilty at the first opportunity.

“He was horrified as everyone must have been as events unfolded,” Mr Dillon said.

Merseyside Police said the dog was seized and humanely destroyed with the consent of the owner.

Detective Constable Beth Flintham said: “This was a horrific attack on a young girl, who suffered serious facial injuries and required hospital treatment.”

“We can only hope that this case provides a warning to dog owners, regardless of breed, about the importance of keeping their pets under control in public places,” she added.

The officer said the force would “act on any information provided about the alleged irresponsible ownership of a dog”, warning that “failing to keep your dog under control can lead to the worst outcome imaginable”.