CLINTON -- Steve O'Brien had in his pocket a Boston Marathon qualifying time he did not plan on using. This former Groton-Dunstable Regional High School and UMass Lowell runner had that 2:46:52 from finishing eighth in the 2012 BayState Marathon in Lowell, the only marathon he has run.

Running Boston was a dream O'Brien, 26, figured he would fulfill eventually. His immediate focus was on training for triathlons. O'Brien qualified for the world half-ironman championship in Las Vegas in 2012. Completing a full ironman is another endurance test on his bucket list.

But in early February his training all of a sudden turned toward this year's Boston Marathon. O'Brien was approached by the Norden brothers, JP, 34, and Paul, 32, of Stoneham, who each lost a right leg to the second bomb explosion near the finish line last April 15.

The Nordens asked O'Brien if he wanted to run for them this year. They had a bib number from the B.A.A. to give out (No. 1,118). He had a qualifying time. So this became the year O'Brien would run Boston for the first time, the year that "obviously has a lot of emotional significance for a lot of people," he said.

O'Brien considers the Nordens family. Their mother Liz is sister of the husband of his mother Debra's sister.


O'Brien knows the brothers from family gatherings. The Nordens were on Boylston Street that fateful afternoon to see a friend finish running the renowned 26.2 miles. Three people were killed by two bombs that wounded at least 260 others. Sixteen of those wounded lost various limbs.

O'Brien was at work last year while the Boston Marathon was being run. He works in the Northboro office of the U.S. Geological Survey and lives in Clinton. On Monday he will race on behalf of the Nordens -- running to bring attention to the JP & Paul Norden Bros. Benefit Fund, set up to defray what will be lifelong medical expenses covered only in part by insurance.

JP and Paul Norden have written a book about their ordeal: Twice As Strong: 12 Seconds, Two Brothers And The Marathon That Changed Their Lives. With their prosthetic right legs, the brothers on Tuesday -- the one-year anniversary of the bombings -- walked part of a fundraising relay over the Marathon route.

"I'm inspired by them," said O'Brien. "That's why I'm doing this. I'm representing them out on the course. I'm not looking for sponsors myself, but I would love people to donate and support them."

O'Brien hopes to run at least as fast his 2:46:52 in Lowell 18 months ago. "I ran a little too aggressively the first half of that race and paid the price," he said.

Despite his late start toward training specifically for Boston, O'Brien feels ready.

"I do triathlons in the summer, so I'm in pretty good shape," he said. "But I had to scramble to readjust my training and get in some longer runs. The B.A.A. has a training website so I glanced at that. I got up to a couple of 23-mile long runs. I did a couple of speed workouts. My legs feel good, no aches or pains. I want to get out and run a lot, but I'm trying to contain my excitement and do what's best for me (and taper back on training) before the race."

O'Brien has an impressive running résumé. He has two MIAA All-State cross-country medals from his days at Groton-Dunstable. He finished 15th in the Division 2 All-State Meet at Northfield Mountain as a G-D sophomore in 2003, and eighth the following year at Gardner Municipal Golf Course. He twice ran in the Division 2 nationals in cross country while at UMass Lowell, from where he graduated in 2010 with a biology degree.

O'Brien last March ran a 1:13:29 while finishing 56th among 3,135 runners at the New Bedford Half Marathon. 

Regardless of his finishing time Monday, O'Brien will have been out there "trying to soak in the experience" and "running for a great cause," so it will be a "win-win."

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