From blue jeans and Crocs to the starting line of the 129th running of the Boston Marathon on Monday.

Gunner Currier, of Enfield, had an unusual introduction to running 11 years ago, but once he got a taste, he seems to have never stopped running, building up from 5Ks to 10 miles and half marathons and marathons.

“I always wanted to run a marathon since I was little but didn’t really think about Boston,” Currier said in a phone interview alongside his father, Rick, who is also his coach on the Mascoma High School track and field team.

When he saw he would be eligible to run two days after his 18th birthday, the minimum age requirement, he decided to make Boston his goal.

“He is probably the youngest runner from New Hampshire and maybe the youngest in the entire field,” Rick Currier said.

The younger Currier, a Mascoma senior, qualified for Boston last August when he completed his first ever marathon, the Tunnel Vision Marathon in Washington state, with a time of two hours and 49 minutes. The cutoff for the 18 to 34 year men’s age group is 3 hours, but this year, Marathon officials ruled that in order to qualify a runner needed to be nearly seven minutes faster than his or her respective qualifying standard.

Currier’s initiation into the world of competitive running at the age of 7 came about unexpectedly. He was with his father at a race in Canterbury, N.H., as a spectator, to cheer on his mother, Tiffany, in the Canterbury Woodchuck Classic 5K.

As the father and son tell it, Currier saw youngsters preparing to run in a one-mile kids’ fun run and announced he wanted to run, even though he was dressed in blue jeans and wearing Crocs on his feet

“He had never run before so I just told him to follow the other kids,” Rick recalled. “He followed a girl who was running the 5K with her mother and ended up running the whole race. His running just took off from there.”

Gunner said when he finished, his first thought was “I want to do more.”

And more he did. Competing in four and five mile races, 10Ks, 12Ks and ten mile runs.

“He was hooked on it,” said his father.

A year after the Canterbury 5K, Currier entered a half marathon at the age of 8 and did a combination of running and walking to cover the 13 mile distance. He ran an entire half marathon at age 9, finishing in just under two hours, despite many urging against someone that young tackling a long distance.

At a 10K race in Hyannis, Mass., Currier met Bill Rodgers, a four-time Boston Marathon winner between 1975 and 1980 and was able to spend some time talking to him about running and in particular half-marathons.

When Currier told him that others were saying he was too young to run, Rodgers gave him different advice.

“Don’t let them tell you that,” Currier said Rodgers said to him. “Just listen to your body.”

Currier likely got his talent and love for running from his father, who ran track in high school and cross country at Delaware State.

Last fall, he placed second in the NHIAA Division III Cross Country meet, leading the Royals to the school’s first ever championship. At a recent high school meet, Currier won the 3,200 and shortly after when his father was getting ready to scratch the team’s 4 by 400 relay because one runner had dropped out, Currier stepped in, telling his father, ‘I feel really great. I’ll take his place.’

The enjoyment he gets from running combined with his competitive streak motivates Currier to get out and train.

“For training, I know what I have to do to get where I want to be,” he said. “I love being outdoors and being able to focus on running only, not thinking about other things.”

Rick said since eighth grade his son has stepped up his commitment.

“His dedication is pretty much top notch,” Rick said. “It is astonishing.”

In the months leading up to Monday’s marathon, Currier put in 70 miles a week but as race day approached, he tapered down the distance.

Though he is excited for Boston, Currier said he is not looking to set a personal record because it is Mascoma’s outdoor track season.

“I don’t want to kill my track season by running a really hard Marathon and taking weeks to recover,” Currier said.

Next year, Currier will run at Franklin Pierce college with his Mascoma teammate, Trevor Maheu; a long way and a lot of miles from that day in blue jeans and Crocs.

Patrick O’Grady can be reached at pogclmt@gmail.com