Still smarting from failing to finish his first Boston Marathon last year when a pair of bombs disrupted the race, Stillwater runner Mike Johnson had the 2014 finish line in sight Monday when he came to a sudden stop.

Struggling to stay on his feet was a man “whose legs weren’t cooperating at all,” Johnson said. Two other runners were already trying to help him.

“I saw that his name was Adam on his bib, and I asked, ‘How are you doing?’ ” Johnson, 47, recalled Tuesday.

“I am going to finish,” came the reply.

And finish he did, thanks to the strong backs and helping arms of Johnson and three other runners who carried the man about 200 yards down Boylston Street to just shy of the same finish line that was rocked by bomb blasts last year.

“We’re going to get this guy in,” Johnson recalls telling his fellow good Samaritans as they struggled down the street, two helpers grasping Adam’s arms and two others taking his legs. Johnson said it was a struggle every step of the way, but the crowd provided a lift. “They were going nuts,” he said.

The foursome was about to stop to get a better handle on Adam when the man announced he was getting on his feet. Near the memorial to the victims of last year’s bombings and the bleachers packed with cheering fans, Adam staggered across the line under his own power.

Johnson crossed, too, and then broke down. “I was just caught up in all the emotion,” he said. “It was just unbelievable. I don’t even know what to say. It was just amazing.”

He never saw Adam — or his fellow helpers — again.

But their selfless act sent a charge through the mass of spectators along the finish — and one through the Twitter universe after photos of them in action were posted by a Washington Post reporter.

Coincidentally, Johnson played a similar role earlier in the race when he assisted an ailing runner who went to the ground at mile 24. Johnson hailed a security person, who with a spectator helped the runner get medical attention. With a jolt of excitement from the incident, Johnson continued his final push.

While that kind of assistance might have been taboo for a pro runner competing for prize money, to many the gesture seemed in keeping with the spirit of the marathon. Especially this year’s.

Reflecting Tuesday, Johnson was incredulous. “There were 37,000 runners, and I get caught on camera and end up on the ‘Today Show,’ ” he said. “If I would have run 10 minutes faster last year, I wouldn’t be here [in Boston] today.”

And he was quick to downplay his good deed. “It wasn’t heroic. I was helping someone else get to the finish. It’s just what you do.”