These are the shocking scenes when two wild stallions battled each other for the right to breed with a group of females in Colorado.
The stallions square off with each other before rearing onto their hind legs and lashing out with 'punches'.
The black horse manages to leap higher than his opponent, allowing him to score better blows against his opponent.
The grey stallion then lands awkwardly as a white female looks on.
The photographs were taken in the Sand Wash Basin in north western Colorado by aerospace company engineer Duane Johnson.
The 52-year-old said: 'Seeing this fight really got my adrenalin going. I felt really blessed to witness such a moment.
'I had trekked to this location specifically to photography the wild horses.
'I stayed off the beaten track and found a location that no one else was visiting. I was the only person to witness this moment.
'The two stallions were fighting over the ladies. The silver horse appeared to be an interloper and the black stallion took exception to that.
'This was not horse play. You could tell they were truly battling.
'At one moment I managed to capture the black stallion leaping into the air and baying with its mouth open, which captures the true emotion of the moment.'
