"Mom, I'm going to give coaching a chance," said Harbaugh, who'd just finished college with a political science degree.
He was sure.
Twenty-four years later, as he was introduced yesterday as the Ravens' new head coach, he fielded questions with aplomb. Then he posed for pictures with family, including Jackie, who harked back to that day in 1984 when her son set his life in motion.
"He would have made a great politician," his mother said yesterday. "He's honest and fair, and he communicates well."
Coaching attributes, all.
Given his gene pool, how could Harbaugh not have picked football? His father, Jack, was a lifelong college coach; brother Jim was a quarterback for the Ravens and other NFL teams. Jackie Harbaugh was a cheerleader in high school, where she dated the team's star, Tom Matte, who went on to play for the Baltimore Colts.
Growing up in Ann Arbor, Mich., the Harbaugh kids hung around practice at the University of Michigan, where their dad was an assistant coach.
"They were gym rats," Jack Harbaugh said of his sons, born 15 months apart. "Jim [the younger] would be outside throwing, and John would be talking to Bo [Schembechler, the head coach], gathering information."
John, then 12, was routinely the victim of team pranks.
"Once I got taped to the goal post; another time I was stuffed in a locker," Harbaugh said. "Who could have asked for a better childhood?"
At home, the boys were typical sibling rivals. Through high school, they shared a bedroom in the family's smallish home and were always tussling about.
"They'd be upstairs wrestling and I'd pound on the ceiling shouting, 'TAKE IT OUSIDE OR I'M COMING UP THERE!' " Jack Harbaugh said.
Mother Harbaugh just shook her head. "I do wish I'd had headphones to block out all their noise," she said.
One winter, the boys made a primitive basket from a coat hanger, hung threads from it and played one-on-one with a Nerf ball in the basement.
'Rational, cerebral'"John and Jim battled over everything, down to who'd get the last piece of meat at the dinner table," their father said.
A favorite trick: When family portraits were taken, the shorter of the boys would wait until the last second to stand on his tiptoes, thereby looking taller than his brother.
"John did the same thing again last week, in photographs at Jim's wedding," Jack Harbaugh said.
The brothers couldn't have been more different, family and friends said. Jim was bigger, louder and impulsive. John was earnest, focused and disciplined.
"Jim was an out-of-the-box guy," their father said. "John was rational, cerebral."
"John wasn't near the athlete that Jim was, but he had this quiet dignity about him," said Tim Anderson, a teammate at Pioneer High School in Ann Arbor. "John was hard-nosed, no-nonsense and extremely bright.
"The fact that he wasn't a star athlete like his brother didn't bother John, and you never thought of him as being in Jim's shadow."
John, a defensive back, was meticulous to a fault, Anderson recalled.
"Once, after practice, we were in the showers when John told me, 'You should always wash your hair first, because otherwise the stuff in your hair will get all over you and you'll have to wash again,' " said Anderson.
"John always thought about the right way to do things."
That anecdote is typical of her son, Jackie Harbaugh said.
"John figures out what works best in every situation and then works to make it right," she said.
What he lacked in talent, Harbaugh made up for in smarts.
"Even then, he was a coach on the field," said Greg Yarrington, another teammate in high school. "He knew what was going on and had the ability to help others in the game with their coverages and their reads."
For one year, the Harbaugh brothers played together in high school: Jim, the hotshot sophomore, and John, the soft-spoken senior.
One game in particular stands out in Jackie Harbaugh's mind.
"It was a Friday night in October, and John went in to play receiver," she said. "The next minute, I heard on the loudspeaker, 'It's a pass, Harbaugh to Harbaugh!'
"Life doesn't get any better than that."
Diverse friendsAs a teenager, John Harbaugh was color-blind in an era when race was still an issue, said Yarrington, who is black.
"He didn't make a distinction about folks. Some of us from the other side of town were a little rough, but John embraced us for what we were," said Yarrington. "He had a diverse set of friends which has probably carried over into his coaching."
For several summers, said Yarrington, Harbaugh singled him out to join him at a retreat for the Fellowship of Christian Athletes, where campgoers weren't allowed to cuss, drink or talk trash.
"That experience made a big difference in my life," said Yarrington, who went on to earn degrees from Cornell and Yale.
Harbaugh attended Miami University of Ohio, where he earned one football letter in his senior year.
"My dad always called it 'the twilight of a mediocre career,' " the Ravens' new coach, 45, said yesterday. "But I am awful proud of that letter."
"John didn't have blazing speed," said Steve Fitzhugh, a cornerback on that Miami team. "He wasn't the biggest, the strongest or the fastest. But he made up for it with hard work and dedication, and the rest of us could all feed off of that."
Said Jack Harbaugh: "John has tremendous energy and an enthusiasm unknown to mankind."
As a college senior, Harbaugh was named honorary captain for Miami's game against Western Michigan, then coached by his father.
On the opening kickoff, Harbaugh - a mainstay on special teams - lined up a few yards from the sidelines where his father stood.
Dad decided to mess with his son's head.
"John had his back to me, but I knew he could hear me," Jack Harbaugh said. "I told him, 'John, we've got a plan and we're coming for you.'
"John just leaned forward and hollered, 'Bring it!' "
For a moment, Jack Harbaugh's allegiance changed.
As the ball sailed downfield, he said, "I yelled to John, 'Go kick some [butt]!'
"Never mind that it was ours he was kicking."