"It'll probably never happen again," Harvick said after McMurray made Ganassi the first team owner ever to win the Daytona 500, the Indianapolis 500 and the Brickyard 400 all in the same year.
"I've always liked him as a friend, and I respect him as a driver," Ganassi said of Harvick, and then burst out beaming -- "and I hope I'll learn to respect him as a historian."
McMurray accounted for two-thirds of the achievement, becoming only the third driver to win NASCAR's two most prestigious races in the same year. Only Dale Jarrett (1996) and Jimmie Johnson (2006) had won the Daytona 500 and the Brickyard in the same year.
Dario Franchitti piloted Ganassi's Indy car to the win here in May, giving Ganassi his first milestone of this season, first owner to win the nation's top two 500s in the same year.
Told of Harvick's prediction this feat won't be repeated, McMurray concurred that "it most likely won't."
It's a trifecta that wasn't even possible until 1994, when NASCAR started racing here. And it hadn't really even been considered until the Ganassi milestone was reached here in May.
McMurray even found a reason for disappointment within the Ganassi organization.
"Chip is just having such a year between the NASCAR side and the IndyCar side, the thing I think of the most is that they almost won the 24 Hours of Daytona [America's biggest sports car race]," McMurray said. "I think they finished second.
"But it's so hard to get both organizations good at the same time," McMurray continued. "This race, the Daytona 500 and the Indy 500 are races of strategy, and you see guys dominate these races and not win."
A blatant case in point -- both for the day and for the past two years here -- was Juan Pablo Montoya, McMurray's teammate. Montoya looked as dominant Sunday as he had been last year, but again stumbled near the end.
Montoya was running away until Sunday's final pit stop, when his crew opted for four tires while most other front-runners were taking two. That dropped Montoya from a commanding lead back to seventh, and he never recovered, even wrecking in his struggle to catch up. Last year he lost on a penalty for speeding on the pit road.
Ganassi had tough humor for Montoya and his crew chief, Brian Pattie.
"What do I say to Juan and Brian?" Ganassi repeated a question, then cracked, "They should have taken two."
McMurray and crew chief Kevin Manion did take only two, and came out of the pits in the lead on the same stop where Montoya fell to seventh.
But Harvick rushed up to take the lead from McMurray with 15 laps to go, and might have had the race won if not for Montoya's wreck that brought out the final caution.
Race teams and race drivers and owners and sponsors, you come into the year and if you're in the IndyCar series you want to win the Indy 500. If you're in the Cup series you want to win here and you want to win Daytona. To win all those in one year is remarkable. It'll probably never happen again.
”-- Kevin Harvick
Those final two restarts were daylight and dark for Harvick.
"On the first restart, it took off great," he said. "We were able to run Jamie down and pass him. Second restart, it didn't take off so great. Just got tight. He drove around the outside of me."
From there, with 11 laps to go, it was clear that only a fluke could cut short the Ganassi sweep of America's three majors of auto racing.
The accomplishment is even more titanic when you consider that at season's outset, the NASCAR side of the Ganassi operation had seemed discombobulated.
McMurray, squeezed out at Roush Fenway Racing, didn't even have a ride until Ganassi signed him as the best available driver to replace Martin Truex Jr.
"Is it surreal? Yes," Ganassi said. "From where we were awhile back -- people had Jamie written off; people had us written off."
Said McMurray, "I'll tell you something that Chip said to me right before I got in the car [Sunday]. He said, 'Let's go out and do this thing.' I said, 'I'll give you everything I've got.'
"He said, 'I know. That's why I hired you. I believe in you.' ... That's what drives me, having somebody behind you."
To climb out of trouble, up to American racing's new trifecta, "You gotta work hard at what you want to do," Ganassi said. "It's the only way I've figured out how to do it ...
"You have to plan your work and work your plan, and have some passion about what you're doing. You have to love what you're doing. I love what I'm doing."
But it's not as if the other teams haven't striven and aspired the same way.
"Race teams and race drivers and owners and sponsors, you come into the year and if you're in the IndyCar series you want to win the Indy 500," Harvick said. "If you're in the Cup series you want to win here and you want to win Daytona.
"To win all those in one year is remarkable," he continued. "It'll probably never happen again."
Ed Hinton is a senior writer for ESPN.com. He can be reached at firstname.lastname@example.org.