Dramatic turn of events as octopus battles crab on sea floor; video

Two divers exploring the Monterey Bay sea floor last week stopped to document a classic showdown between predator and prey: a red octopus versus a swimmer crab.

The larger octopus possessed a clear advantage over a sandy bottom with no immediate shelter for a crab with only its feeble claws for defense.

But the crab, its claws outstretched for battle, proved surprisingly evasive as the octopus tried repeatedly to smother the crustacean with its powerful arms and mantle.

Patrick Webster and Connor Gallagher had framed the skirmish with bright lights at a dive spot known as the Breakwater, at San Carlos Beach.

As they awaited the outcome, however, a harbor seal charged furiously into the arena and devoured the octopus, saving the crab's life.

"We saw him earlier in the dive, but by the time Connor found the octopus, we hadn’t seen him in a while and figured he left to go hunt elsewhere," Webster, who works for the Monterey Bay Aquarium, told GrindTV. "He was entirely out of my mind when he swooped in and ate the octopus, so I was completely surprised."

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The seal, however, is a regular in the area, nicknamed “Whiskers,” who has learned to hunt in areas illuminated by dive lights. Webster and Gallagher captured the attack with two camera angles, and posted video footage to Facebook and Instagram.

“A showdown between predator and prey, locked in a deadly dance,” Webster wrote in his Instagram description. “You’ll never believe what happens next!!!”

For those wondering about the inserted audio commentary, it's from Jim Ross during the famous Hell in a Cell professional wrestling match, between The Undertaker and Mankind.

Somewhat fitting, considering the emphatic slam carried out by the seal on the unsuspecting octopus.