As 21-year-old Haley Klinger neared the finish line at Love Run Half Marathon in Philadelphia, her legs started to buckle.

Video footage from Sunday’s race shows the young woman stop, grimace and reach down toward her feet. Without missing a step, two fellow runners grab her under her arms and carry her along with them.

That was the moment triathlete Joseph McGinty, 31, turned around to find his training buddy, 45-year-old Bryan Crnkovic. He saw Crnkovic and the other man, who has not been publicly identified, helping an exhausted woman finish the race.

So McGinty ran back and scooped her up in his arms.

“I saw she almost fell to the ground, so I grabbed her and said, ‘Let’s go,’ ” McGinty told The Washington Post on Tuesday. He added: “It was instinct. Someone was in need and I wanted to help.”

Feet from the finish line, McGinty set Klinger down to let her cross it on her own. Medics put Klinger, who was exhausted and dehydrated, in a wheelchair.

Klinger, a junior nutrition student at Messiah College near Grantham, Pa., said “Love.Run.Philly” was her first half-marathon. She had spent a couple months training for it and she wanted to finish.

“I wasn’t sure I could do it on my own but when they came, I was really grateful because they helped me push my limits,” Klinger said of her fellow runners.

She said when McGinty picked her up, he told her, “We’re going to finish this race together.”

“I wasn’t completely aware of what was happening,” Klinger said. “I really just wanted to finish the race — I just wanted to complete it and then sit down.”

Klinger crossed the finish line in 1:54:51, according to the race results. Crnkovic and McGinty, who said they were running the race for training, finished in 1:59:23 and 1:59:28, respectively. They said they had no idea a video showing a simple good deed would catch fire on social media.

On Sunday night, McGinty, from Philadelphia, and Crnkovic, from Drexel Hill, Pa., got a call from a friend who told them the video had swept across social media.

“It’s kind of surreal,” McGinty said. “You just help someone in need; you don’t expect all this.”

Crnkovic said it is not unusual for runners to try to help others who are struggling to finish a race — it’s just that, this time, the moment was captured on film.

“I’m becoming famous because somebody caught 15 seconds of me doing the right thing,” he said. “It’s something that we do all the time. In marathons and triathlons, if somebody’s faltering, there’s always somebody else saying, ‘Come on, you can do it.’ ”

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