Once a potential donor enters the bone marrow registry, the chances of that person being an exact match for a person in need and donating are about 1 in 540, according to the website of the Be The Match organization. A bit of math: What are the chances of not one, but three people living in the same house being chosen as matches?

One in over 157 million — slightly better than your chances of winning the Powerball lottery.

Over the past two years, three members of the Yale football coaching staff have hit a lottery of sorts, as each has saved a life by donating marrow.

Assistant Coach of Football Operations Chris Gennaro, Outside Linebacker Coach Paul Rice ’10 and defensive intern Zach Wigmore, who live together in a New Haven house, have each donated peripheral blood stem cells during their time at Yale to patients they did not know. Rice’s and Wigmore’s donations in New York City were within a month of each other at the end of last year.

“When Zach [Wigmore] and I heard that we were possible matches at the same time, it was pretty unique,” Rice said. “I told the nurse that the three of us live together, and she remembered Zach. They all thought it was pretty cool.”

The three housemates’ fortune exemplifies the success of the Yale community as a whole in donating to those in need. The Mandi Schwartz ’10 Marrow Donor Registration Drive, kicking off for the sixth time tomorrow, has found at least 23 life-saving matches out of the approximately 3,800 people it has registered.

But that count does not include Gennaro and Wigmore, who did not enter the registry at Yale. Gennaro, a former University of Maine kicker and punter, signed up for the cheek-swab procedure in a similar drive at his school, and Wigmore joined with a few brothers from his fraternity at the University of Michigan.

“I was on my way to lunch at the Student Union, and they were having a marrow drive, so we [signed up],” Wigmore said. “It was more luck of the draw than anything else.”

Rice was a junior defensive back and linebacker at Yale during the 2008–’09 season, the year that Schwartz first learned that she had leukemia and did not have a match.

He participated in the first registration drive that year when assistant head coach Larry Ciotti introduced the idea of the drive to Yale.

“Coach Ciotti did a great job educating everyone about what it was, why we were doing it and how easy donating marrow had become,” said Rice, who would go on to captain the Yale team in the fall of 2009.

Gennaro added that the drive would not be as successful as it has been if Ciotti had not been its organizer.

Gennaro was the first of the three to donate, having discovered that he was a potential match in July 2012, just two weeks before starting his job at Yale. He donated in August during a full month of preseason practices, but said that he only missed one because of donation procedures.

Wigmore and Rice were also in the middle of football season when they found out last October that they could be matches. Within weeks, doctors confirmed to both of them that they were the best possible matches for their recipients.

Wigmore’s doctor asked to do the procedure the day before the Harvard-Yale game, but he was able to push it back by a few more days, Wigmore said.

Because their recipients were not ready to receive the stem cells as soon as doctors had planned, Wigmore and Rice were both able to do the procedure after the season was over.

“[The nurses] do such a good job of making [the donation] accommodate folks’ schedules, really helping everyone out,” Wigmore said. “It was pretty impressive how well they run it.”

Gennaro, Wigmore and Rice were not able to find or meet their recipients after the donations because the recipient can choose whether or not to get in contact, Wigmore said. Doctors could only tell them their recipients’ sex and age, which ranged between 40 and 74 years old among the three. All three patients had leukemia.

The three donors stressed the ease of their procedures despite being in the middle of their football seasons. They all donated by peripheral blood stem cells, which requires blood removal instead of direct marrow removal by surgery.

“If you can give an extra day, an extra week, an extra month or year, or hopefully even more than that, to someone who’s sick and has a family, then I think it’s absolutely worth it,” Rice said. “It’s painless on your part, just organizing when you’re going to go to all the appointments and scheduling the date.”

Because of their experience with donating marrow, all three coaches serve on a marrow drive committee that helps organize the event alongside Ciotti.

Gennaro has sent emails for the drive to the Yale student body, while Wigmore supervises the football players helping out with the drive.

“Their participation has bolstered the drive,” Ciotti said of the three coaches. “They have first hand experience to be tested, to be a perfect match and to actually save a life. Their passion has been passed on to the Yale football team.”

This year, Ciotti and the rest of the football, women’s hockey and field hockey teams are attempting to get 1,000 people registered, which would be a record among schools in the “Get in the Game. Save a Life.” program.