It was so simple for Cameron Lyle to join a bone marrow registry two years ago that he gave it little thought after the inside of his mouth was swabbed.

Then came the call: he was a match for a man in need. Lyle, a University of New Hampshire shot putter and discus and hammer thrower, had to make another decision, one that would end his college career.

“When they first told me, I was like, ‘OK, cool. I’m definitely going to do it,'” Lyle said (via ABC News). “After that I kind of went to tell my coach and then I realized slowly that my season was over.”

Lyle, who called the decision a “no-brainer for a decent human,” will donate marrow today at Massachusetts General Hospital to help a 28-year-old man who has acute lymphoblastic leukemia. Without a transplant, Lyle said the man was expected to live only six months. Lyle won’t be allowed to lift more than 20 pounds above his head for a few weeks after the marrow is taken from his pelvis.

“It’s just a sport,” Lyle, who is from Plaistow, N.H., said. He competed in his final meet last weekend. “Just because it’s Division I college level doesn’t make it any more important. Life is a lot more important than that, so it was pretty easy.”

Lyle and the bone-marrow recipient must remain anonymous to one another for a year, then can sign consent forms to reveal their identities — a formality given how much attention Lyle is getting.

“I’d love to meet him some day,” Lyle told eagletribume.com. “He’s not that much older than myself. I just can’t imagine what he’s going through.”

This morning, he tweeted:

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