A 582-pound blue marlin, one of the largest caught in San Diego waters, was hooked last month and taken to — what else? — the Marlin Club on Shelter Island.

The big fish was caught Oct. 23 by Sean Mulrooney of Ramona, along with his brother, Brennan Mulrooney of Santee.

The marlin was a total surprise to the fishermen, who originally set out to fish for bluefin tuna near the Coronado Islands aboard Listo, a 27-foot Stringari skiff built and owned by Mark Henwood of Clairemont, who captained the vessel.

The Mulrooneys’ grandfather Art Carey was a member of the Marlin Club in the 1930s, and the men often went marlin fishing in their younger years.

The 582-pound blue marlin awaits weighing on the swim step of the skiff Listo after being taken to the Marlin Club on Shelter Island. (Provided by Sean Mulrooney)The 582-pound blue marlin awaits weighing on the swim step of the skiff Listo after being taken to the Marlin Club on Shelter Island. (Provided by Sean Mulrooney)

Until the 582-pound fish was brought closer to the shore, the anglers thought they had hooked the more common striped marlin. They also didn’t know its weight until it was weighed upon reaching the Marlin Club, according to Sean Mulrooney.

The fish was reported to be the largest blue marlin weighed at the club since a 662-pounder in 2015.

Sean said the men texted their return to shore after the fishing trip and a crowd of friends and family members waited for them at the Marlin Club dock.

The fish was so heavy that the crane used to lift it broke and collapsed onto the boat. Two people were injured.

The catch resulted in 300 pounds of smoked marlin, split between Sean and Henwood.