AURORA (KUSA) - A young boy from Aurora is one of the fastest 9-year-olds in the world.

Griffin Mazeski just set a single age record for running a half marathon in 1:33:43.

That's about a minute faster than the record set by a 9-year-old from St. Pete Beach, Florida according to the Association of Road Racing Statisticians.

"It was pretty hard and I didn't know if I could really break the record because I didn't feel that prepared coming into it," said Griffin.

Griffin traveled to San Diego with his family for America's Finest City Half Marathon and 5k last weekend.

The family of four started the race together, but Griffin and his dad, Brian, eventually broke away from his mother and 12-year-old sister.

The father-son pair ran 11 miles together before Griffin pulled ahead and finished the last few miles solo.

"The first 11, I mean, I felt really good and I was going under my pace that I wanted and I felt really calm and I could breathe easily, but at mile 12 there was a really long hill and I sort of died out on that," he said.

But Griffin kept on pushing, in fact, he tells 9NEWS he actually tried to speed up his pace to finish and reach his goal of setting a new record.

Griffin waited at the finish line for his dad before getting his finishing medal, and official time.

The pair found out together that he had broken the record.

"I sort of climbed up and hugged him, and he told me that I had it and I was really happy. I was really excited that I met my goal," he said. "It's just hard to think, but I felt crazy good."

Wednesday, August 23, was Griffin's birthday. If you can believe it, the now 10-year-old WANTED to competitively run the 13.1 mile race for his birthday.

"I thought it would be a cool experience and I think that it would be a really big accomplishment," he said.

Well Griffin, you're right, that is a great accomplishment - congratulations Griffin and happy 10th birthday!