THIS is the incredible moment a woman was saved by an unlikely underwater saviour as a shark menacingly swam towards her.

Marine biologist Nan Hauser, 69, says she was left in tears after a heroic 50,000-pound humpback whale came to her rescue.

The majestic creature incredibly shielded Nan Hauser from a tiger sharkCredit: Caters News Agency

The heroic humpback whale ushered the marine biologist to the safety of her boatCredit: Caters News Agency

The entirety of the extraordinary encounter was caught on cameraCredit: National Geographic for Disney

Her extraordinary encounter was caught on camera and has now been broadcast as part of National Geographic’s annual Shark Week.

Nan had been exploring the stunning coast off Muri Beach in the Cook Islands when she ran into the two creatures below the surface.

The whale expert was admiring the ocean when she suddenly spotted something sinister heading her way – a terrifying tiger shark.

Nan recalled: “It’s moving fast and it’s coming towards me.

“I know and the whale knows that this is a serious situation. I wanted to get out of the water.”

In the footage from 2017, the fearsome beast is seen speedily swimming towards the helpless snorkeller from the depths.

Out of shot, the hulking humpback whale was frantically slapping its tail to warn the 15ft long shark off from Nan.

She continued: “All of a sudden, I was swooped up by the whale that had been pushing me and now he’s got me right on the front of his face.”

The former nurse then alerted the crew on her boat as she was thrust up to the surface, before she tumbled back underwater.

She continued: “Somehow I always sort of knew with my job that I’d probably be 𝓀𝒾𝓁𝓁ed by a whale, so I thought is this the day?”

Dramatic video shows Nan desperately grappling with the whale as she tries to dodge its hefty pectoral fins.

The experienced snorkeller was trying to avoid getting lodged underneath them and trapped underwater – as well as the risk of broken bones and ruptured organs.

Armed with only her snorkel and mask, she realised her breathing apparatus would fail if she was dragged under by the whale.

But incredibly, the mammal had taken on the role of Nan’s blubbery bodyguard and shielded her from the jaws of an incoming shark.

She recalled: “I suddenly realise that the shark is coming up. Right below me. The whale pushes me back to the boat.”

By nudging her with its head, bumping her with its belly, and swiping at her with its powerful pectoral fins, the gentle giant miraculously managed to transport her to safety.

A relieved Nan is then seen clambering back on board the vessel while the whale keeps a watchful eye on her from metres away.

“I look and he’s right there next to me, protecting me,” she said. “I cried.”

The whale then majestically dives back down to the depths, leaving his damsel in distress overcome by emotion.

The heart-stopping footage was shown during the Saved From a Shark show by National Geographic.

Nat Geo Wild’s annual programming event SharkFest begins on July 16 at 8pm with When Sharks Attack Season 9.

We previously told how a man who was attacked by a rare shark species was saved by a valiant pod of dolphins.

Martin Richardson was bitten five times by a Mako shark off the coast of Egypt – but while floating in a pool of his own blood, he was rescued by the mammals.

Nan was left in tears after her blubbery bodyguard rescued herCredit: National Geographic for Disney

Heartwarming footage shows how the whale escorted the snorkeller back to the boatCredit: National Geographic for Disney

She was seen hiding behind the hulking whale as the shark grew closerCredit: Caters News Agency