BOSTON (CBS) – Dave McGillivray got to relive one of the greatest moments of his life at Fenway Park Thursday. He took a victory lap around the field before the Red Sox-Indians game, marking the 40th anniversary of his 1978 “Run Across America,” what Runner’s World magazine called “the first cancer-fund-raising run.”

Dave McGillivray runs in Fenway Park, August 23, 2018. (WBZ-TV)

“It was a defining moment in my life, right here at the park,” he told WBZ-TV. “Now I have a mission, to continue to do these things, to give back.”

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Running an average of 45 miles a day, McGillivray ran from Medford, Oregon to his hometown of Medford, Massachusetts, where his support trailer died. But it’s also where a crush of fans and that year’s Boston Marathon champion, Bill Rogers, were waiting.

From there, he ran to Fenway, celebrating a feat some said was impossible.

Dave McGillivray finishing his Run Across America in 1978. (Photo credit: Dave McGillivray)

“I knew in my own heart I had trained really hard and I earned the right to do it and I was going to do it and I had to get to Fenway to prove it,” he said. “There was no better place, no better place, because… my goal was always to play second base for the Boston Red Sox. Well, if I can’t play on the field, I’m going to run on the field.”

Dave McGillivray finishing his Run Across America in Fenway Park in 1978. (Photo credit: Dave McGillivray)

The Red Sox fans loved it! But his boss at a benefit consulting firm was less impressed, firing McGillivray for not returning to work the next day.

“I was fired and it was the best thing that ever happened to me in my life,” he told WBZ. “My first reaction was – ‘That’s the thanks I get for running across the continent for sick kids?’ And then I thought, ‘I’ve gotta make something out of this.’”

Since then, he’s run and organized more than 500 events, including the first-ever marathon inside Fenway Park, events that have raised millions for charity.

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“All these things, now 40 years later, have come back to me in the last couple of months. It just makes me feel proud that I am able to do it and more than anything, that I’m still doing it,” he said.

Dave McGillivray. (WBZ-TV)

McGillivray, the race director for the Boston Marathon, celebrated his 64th birthday Wednesday and with this anniversary run, he’s aiming for a new goal – to raise $100,000 for the Jimmy Fund in a month, roughly what he raised by running across the country in 1978.

For him, this is not just about running.  It’s about a life plan.

“Set goals, not limits,” he said.

He’s also set another goal. Thirty years ago McGillivray helped create the Jimmy Fund walk, but he’s never actually walked it. He’s run it seven or eight times. But next month, he’ll finally walk it with his family. Just walking, he says, could make it his toughest challenge ever.

His second annual Fenway Park Marathon is this Friday at 5 p.m.

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