[matthew fuller]

He looks exactly like a mastiff to me, NOT a bullmastiff.

www.animalplanet.com/breed-selector/dog-breeds/working/mastiff.html

Tried to post the image, but that wouldn’t work for me right now...

[trisham]

It doesn’t look like a bullmastiff to me, either.

[Nonsense Unlimited]

There is no way to know exactly what the dog is without seeing papers (if it even is a pure breed and has then). Here are some things to compare ...
This is the dog in question.


This is the picture of the Mastif you referenced.


This is a picture of two Presa Canarios, one uncropped, one cropped.

Here is a File Basiliero (I owned 3 of them, and this one looks almost exactly like the male I had).


The one think to look at is the set and length of the ears. The Fila's ears fall back (more hound looking) when they are relaxed as the dog in the original picture seems to be.
I'm not excusing any breed or breeds, just trying to help people see the different. :)