It took 90 minutes to land, 13 men to heave it out of the water... and weighed 55 stone when they finally got it to the scales.
So it's little wonder that when Ian Welch first hooked the record stingray, it almost pulled him into the river.
Mr Welch, who weighs 111/2 stone, said: 'It dragged me across the boat and would have pulled me in, had my colleague not grabbed my trousers.'
The angler, from Aldershot, Hampshire, was fishing in Thailand when he landed the ray, which is the biggest freshwater fish to be caught with a rod.
The biologist was helping with a stingray tagging programme on the Maeklong River, when he hooked the fish.
'It buried itself on the bottom. I tried with every ounce of power but it just would not budge. After half an hour my arms began shaking and after an hour my legs went.
'Another 30 minutes went by and then I put a glove on and physically pulled the line with gritted teeth.'
Once the stingray was off the bottom, it was relatively easy to lift it 30ft to the surface, said Mr Welch, 45.
'As soon as we saw it there was just silence because everyone was just in awe of this thing.'
Eventually the group towed the ray to the bank, put it in a paddling pool, tagged it and took DNA, before releasing it.
The giant freshwater ray is listed as a vulnerable species by the International Union for Conservation of Nature.
This one, 7ft long and wide, with a tail of 10ft, had its venomous barb wrapped in cloth on the bank.
Mr Welch said: 'I was exhausted afterwards. I did very little for the rest of the day - and just had a cold beer