Sure enough, next day in Cup, Larson came out of nowhere at the end to become Busch's last challenger for the win.
Coming out of nowhere was what caught Ganassi's eye in the first place, at Daytona in the notorious season-opening Nationwide race of 2013. It wasn't when Larson's car was torn in half and his engine went into the grandstands near the flag stand. It was what Larson did in the moments before, to get into position to go all out for the win.
"I remember watching him in the race, hearing all the time 'how special he is, how special he is,'" Ganassi recalled, "and he's running around ... 14th, or 12th, and I thought, 'What the hell is so special about this kid?'
"Sure enough, at the finish line, he was right there -- of course he [at least his car] was here and there at the finish line. ... Be that as it may, that to me was special."
Often, "He gives you the impression he's dillydallying in the middle of the pack, not paying attention," Ganassi said. "Always at the end, he's where it seems to matter to be."
You just don't come out of nowhere at little Martinsville Speedway, the next stop on the Cup tour, for Sunday's STP 500. It's NASCAR's smallest track, and it ranks alongside Darlington as the most difficult to adapt to. It's maddening for a newcomer. The traffic is too jammed, too often, in what is more NASCAR's answer to a carnival bumper-car ride than a race.
All Larson wants Sunday, he said on an ESPN.com live chat Tuesday, is to "stay out of trouble and stay on the lead lap."
But that's typical Larson understatement and humility. He has raced there but once, and briefly, last fall, falling out early with a blown engine in a subpar car.
So if he shouldn't flash out of nowhere at the end, that wouldn't tell you much about his future, and NASCAR's future.
But if he should, that would tell you everything.