good story here behind paywall, I'll quote a couple relevant parts https://theathletic.com/619436/2018/10/29/buckley-david-prices-transformation-into-boston-icon-complete-now/
That’s when Price, caught up in the moment, pulled the official “2018 World Series Champs” cap off his head, reared back, and fired it high into the air toward the crowd beyond the protective netting. As the mob fought for the cap, Price disappeared into the dugout.
“I don’t know why I did that,” he said later. “We have a lot of Red Sox fans here. And hopefully one of them got that hat and they can tell that story for the rest of their life.”
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Turns out Price’s “2018 World Series Champions” cap did wind up in the hands of a Red Sox fan. And for those of you who are into symbols, feel free to look at that cap as a handshake that’ll forever bind Price with Red Sox fans from coast to coast and well beyond.
Price’s cap didn’t wind up with some cranky Sox fan who’d been booing the guy for three years, wondering if he’d ever win a postseason start. Instead, it went to someone who never wavered in his belief Price was going to pitch the Red Sox to a World Series championship.
We’re talking about Cole Flashner, 23, a Needham native whose family relocated to California when he was 13 because it had been decided that a milder climate might be more agreeable for his mother, who has multiple sclerosis.
“Catching this cap is one of the craziest experiences of my life,” he said. “I can’t believe we won the World Series and I’m just happy to be part of it.
“He’s coming off the field, and I’m just cheering for Price,” he said. “All of a sudden he just throws up his hat, it goes over the fence, it comes gliding down the netting. Some guy tries to swoop in and grab it, real quick. And I just got it. Insane.”
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“I’m a very big fan of his work, and I’m really, really happy to see him in a Red Sox uniform,” he said. “And I’m a glass-is-half-filled kind of guy . . . I believed he would eventually prove himself in the postseason and he proved that this year. And he obviously has the potential to keep doing that.”