The more he thought about it, though, the more he warmed up to the idea, calling it "one of those one-in-a-million experiences."
Scully will be joined by his wife, Sandi, for the 5 1/2-mile ride down Colorado Boulevard in Pasadena on Jan. 1. He was introduced as grand marshal on Thursday at Tournament House.
He told The Associated Press in an interview before the announcement that his first reaction to being chosen was, "Wow."
Then came some doubt.
The intensely private Scully is rarely seen publicly after the Dodgers' season ends, preferring to spend the winter months at home with his wife of nearly 40 years and their extended family.
The prospect of being the center of attention for several hundred thousand parade revelers and a worldwide television audience had Scully thinking carefully. His wife provided some gentle persuasion.
"She kind of pushed him that on behalf of the Dodgers and on behalf of the fans he needed to do this," Tournament of Roses President R. Scott Jenkins told the AP.
"He is such a humble person that I feared he would not want to be out there and get the accolades. He spends the summer applauding our sports heroes.
Scully questioned why he would be chosen as grand marshal, an honor that has previously gone to such luminaries as Frank Sinatra, John Wayne, Walt Disney and Mickey Mouse. Dodgers star Jackie Robinson was posthumously chosen in 1999, and home run king Hank Aaron served in 1975.
"I don't take it as any personal, great accomplishment," he said. "I only take it for what it is, the fact that I've been doing this for so long here and the Dodgers are doing well. It's not me."
That humility, along with Scully's career accomplishments and his integrity, is why Jenkins chose Scully.
"With Vin Scully you do know what you're going to get," he said. "That's why I think he's held in such high esteem."
Jenkins grew up in Los Angeles in the 1960s, and spent his summer nights falling asleep to Scully's dulcet voice over a transistor radio on his pillow.
"I have very fond memories and I'm sure I'm not the only one," he said.
Scully, who turns 86 in November, recently announced he will return to the booth for a record 65th season in 2014. He began his broadcasting career in 1950, when the Dodgers were in Brooklyn. He works alone calling all nine innings of the team's televised games, with the first three innings simulcast on the radio.
The Dodgers lead the National League West standings, and are headed to their first playoff appearance in four years.
Presiding over the floral spectacle as grand marshal will bring Scully full circle. He has fond memories of doing parade commentary for ABC in 1969 with "Bewitched" star Elizabeth Montgomery and he rode on the Dodgers' float in recent years.
He recalled making the turn from the street where the entries are assembled onto Colorado Boulevard.
"It took my breath away because it was a canyon of people on either side," he said. "I've never seen anything quite like that. In the beginning I was really carried away with the sight."
Scully's family includes five living children and 17 grandchildren ranging in age from 6 to 22. But they won't be in the parade,
"We'd have to have a float," he said. "That would really inconvenience a lot of people."
As part of his duties, Scully will flip the coin before the 100th Rose Bowl game later that day. He'll also participate in various Tournament of Roses events leading up to the parade that carries the theme "Dreams Come True."
Used to working nights calling baseball, Scully will have to be up extra early on New Year's Day. He will join Jenkins and their wives for a 6:30 a.m. breakfast at Tournament House before lining up for the parade.
Scully joked that if his arm gets tired waving at the crowds for about two hours, "I'll have my wife do it."