Big-game fisherman and Daily Telegraph fishing columnist Al McGlashan got the highlight of his career Friday when he stumbled upon the carcass of a nearly 13-foot squid off the coast of New South Wales, Australia.

"In all my time on the water -- and I've spent 200-plus days out there -- I've never seen anything like it," McGlashan told The Grind in a telephone interview.

According to the Australian Broadcasting Commission, McGlashan was unable to lift the squid to the boat due to its size, but believes the animal must have died recently, as its color was still a vibrant orange.

“They’re sort of one of those mythical things,” McGlashan told Sydney's ABC. “You hear those stories about ancient mariners getting attacked in their boat ... and you only hear about the very occasional one being washed up down in Tassie.”

Australian Museum squid specialist Mandy Reid told the Telegraph the squid was probably either killed by a sperm whale or died of natural causes, citing the species' typically short lifespan.

"Most squid only live for a year, they grow extremely quickly," Dr Reid told the paper.

And if the find wasn't interesting enough on its own, McGlashan's deep sea monster became feed for a large blue shark as he was filming the floating carcass.

"It hoed into the squid straight away and didn't care a bit that it was right next to us," McGlashan told the Telegraph. "It was taking great chunks out of the squid in one bite."

WATCH: