Little did he realize that it wouldn't be too many years down the road before he would be playing on that same stage with legendary Opry member Bill Monroe, the recognized founder of bluegrass music.
McCoury and his own band members last week thrilled Augusta bluegrass fans with their great playing and vocalizing at the Imperial Theatre.
Just before his return visit to Augusta, McCoury talked about being in Monroe's Bluegrass Boys band.
"Bill (also known as Brad) Keith and I auditioned for Bill the same day in March of 1963 at the National Life & (Accident) Insurance building on Seventh Avenue in Nashville," McCoury recalled.
"We both played the banjo and guitar. Bill told us, 'I need a lead singer and guitar player and banjo player in the worse way,' and he decided to have Bill (Keith) play banjo and have me play guitar and sing lead on some songs. Bill Keith's full name was William Bradford Keith, so Monroe said, 'I don't want to have two Bills in my band, so I'm going to call you 'Brad.' "
Keith ended up being a Bluegrass Boy in Monroe's band for eight months, and McCoury stayed a year.
In addition to playing guitar and singing lead, McCoury also drove Monroe's tour bus a lot, especially at night.
"That was in the days of two-lane country roads and no interstate highways," McCoury said. "Monroe had bought a bus from (country music stars) Johnny Wright and (his wife) Kitty Wells. I remember us going on that bus in one series of dates from Miami to Tampa, Fla., and then on to New York City and then to Wheeling, W.Va., and on to Los Angeles, and then back to Nashville.
"I remember driving on the Pennsylvania Turnpike, the Sunshine Parkway in Florida and the Will Rogers Turnpike in Oklahoma. You didn't get any really good roads until you got out West."
He remembers also the long-standing feud that Monroe had with his former band members, banjo player Earl Scruggs and guitarist Lester Flatt, that resulted when the two left Monroe's Bluegrass Boys to form their own successful Flatt & Scruggs band.
"One time we were at Ryman Auditorium for an Opry show, and I saw Bill starting down this ramp in a narrow hallway while at the same time Lester started on the ramp from the other direction. They walked right by each other with their noses in the air and not saying anything.
"There weren't many dressing rooms in (the original) Ryman Auditorium, but Bill had his own and Roy Acuff had his own, and Flatt and Scruggs couldn't use either one!"
Over the years, McCoury saw Monroe change a lot from his usual stoic attitude before his death in 1996.
"He wouldn't talk to people much in all of his early years," McCoury said. "I think he was just shy. But when he got older, he loosened up. I think he saw other bluegrass bands and musicians as competition for many years.
"But when the bluegrass music festivals started growing in popularity, he realized that so many of those musicians had worked for him and was carrying on his legacy."
LEESVILLE SHOW REMINDER: The Haynes 4th Saturday Bluegrass Show will be from noon to 9:15 p.m. Saturday in Leesville, S.C., on the grounds of historic Haynes Auditorium adjacent to Leesville Park.
Admission is free with food and soft drinks being sold to benefit Ridge Christian School. Take your lawn chairs.