Paloma Werner and Ralph Motes were on a whale-watching trip off Cape Town in South Africa in their 33ft yacht when they were treated to the shock of their lives.
The middle-aged South African sailors, who were drifting on the waters with their engine turned off, saw a 40-tonne and 33ft whale spring out of the water and snap the mast before dipping back into the water.
The southern right whales have poor eyesight and navigate through sound. However, their sonar is also relatively poor when compared to other kinds of whales.
"Our boat's engine was off and so the whale just didn't know we were there," Ms Werner told BBC, insisting that she still still loved whales.
However, contrary to this, there are some other reports that claim that the boat threatened the animal by going closer than the 300-metre exclusion zone set aside by the marine authorities.
Whatever the reason, the South African whale-watchers have now realised how "lucky" they were in escaping the incident unharmed.