He was one of 130 children at the Southern Reservoir between 9am and noon for the annual Otago Fish and Game Council's Take a Kid Fishing event.
His 5kg trout looked almost as big as he did, and Blake was thankful for a little help from a nearby council ranger.
"My rod bent right over and the fish took off, so he helped me reel it in and told me what to do.
It took about 10 minutes to get on shore," the Big Rock Primary School pupil said.
Blake had been fishing for about half an hour when he hooked the winning trout, one of about 10 surplus brood stock from Macraes Trout Hatchery released into the reservoir.
It was the second fish he had caught and by far the largest.
With dinner in the bag, Blake's family spent the rest of the morning relaxing as those around them hoped for a bite.
Those with less luck at least had the chance to marvel at Blake's catch.
A further 130 children took to the reservoir on Saturday for the competition, held to coincide with the start of school holidays and the new fishing season.
Otago Fish and Game Council operations manager Ian Hadland said about 50 trout, including three brood stock, were hooked on Saturday and about 30 yesterday.
More than 400 trout had been released into the reservoir, which could only be fished with lures because it was a drinking water source.
From today, children under the age of 12 can fish for free at the reservoir and other freshwater spots, while older children and adults need a licence.
The fishing season runs until May 31.