Who do you think would win in a fight?

Hi everyone, this is my second poll and I'd like to know who you think would win if a strong adult male human would fight a strong big dog (pitbull or rottweiler for instance).
I've asked this question numerous times in person and most of the times people said the dog would win.
They thought this simply because the dog has teeth, and the human has nothing.
I disagreed because I think the human could inflict some serious damage with his feet, fists, fingers and maybe more, if he really wanted to.
It's a strong dog so I chose male human because males have a bit more physical strength than females on average, I do not mean to be offensive.
I've seen plenty of video's of big dogs attacking humans and usually it just went for a leg or an arm (not like cats go for the throat).
While the human is shouting for help most of the times other people would hear this and beat the dog off.
But I'm talking about a life or death situation, fight or flight, where the only option would be fight or get killed by this big dog.
And the human would know no fear and be smart, by for instance going for the eyes with his thumbs, or the throat.
And before you ask, the man cannot use objects around him and is dressed in normal clothes, but no iron boots or anything like that.
Just his strength, intelligence and his body.
So who do you think would win in a face-off?
Adult human male or a fully grown agressive big dog?
The dog could be wild but not be trained by humans to fight, because then it would be a human-trained dog and that could possibly help him in this standoff.
Tell me what you think :D