Jennifer Lopez comes face to face with pregnancy test-eating dog at premiere

There's no denying Jennifer Lopez was on sparkling form in a gorgeous one-shoulder Gianfranco Ferré gown at the LA premiere of her new film The Backup Plan.

But that didn't necessarily mean she was the focus of all the attention. 

The actress and singer had to share the limelight with one of her co-stars from the romcom – Nubbins the dog.

In the film, the adorable Boston terrier plays her dog Nuts, who inspires her character Zoe to set up Hudson Mutts, a pet boutique which caters to pet adoptions and environmentally-conscious pet care.

But that's just a side story to the main plot - Zoe decides to follow her dream of becoming a mother by using a sperm donor. But on the day she goes for artificial insemination she inadvertently meets the man of her dreams.

The trailer for the film shows Nuts causing trouble at a key point – when he tries to eat poor Zoe's pregnancy test.

Nubbins, who joined his on screen 'mum' and her husband Marc Anthony on the red carpet, is just one of three rescue dogs playing the part of the special needs pet.

In the film he walks with the aid of two wheels, but in real life the pooches were all able bodied.

J Lo was full of praise for Nubbins and his co-stars, named Nip and Tuck. "One was good at faces, one was good at walking in the chair, and one was good at moving his head and fighting with you,' she said.

"They were all very talented. It was fun. Sometimes you just have to wait until they get it, but it was challenging."

The dogs were all trained over a number of weeks by trainer April Macklin, who coached the dogs who appear in Marley & Me