First let's get this cleared up: games are not won and lost by one player. Football's just not that kind of sport. For any measure of success, 11 separate pieces must form one cohesive force.
The linebacker makes the tackles because the nose guard occupies his would-be blockers, just as the running back carves through a defense because the offensive line provided the hole.
These truths are elemental to the sport.
Everybody got that? It takes a team to win. It always will.
Now that that's settled, let's not kid ourselves: Gainesville won Friday night because it has A.J. Johnson on its team and North Hall doesn't.
It's that simple. I'd like to put it some other way, but it wouldn't be the truth.
That's not to say he won the game alone: Gainesville's defense was aggressive and opportunistic, freshman quarterback Deshaun Watson was composed beyond his age, the offensive line blocked well, and the running backs ran hard.
But without Johnson, it wouldn't have been enough.
On this night, his presence accounted for more than the seven-point difference on the scoreboard. He solidified the Gainesville defense and ran with a ferocity that needs to be seen to be understood.
And for the Red Elephants, every tackle he made and broke was necessary, because North Hall refused to go away.
In the first half, the game couldn't have been more even. In yardage, in talent, in missed assignments and clutch plays, when red lined up across from green, he was faced with his equal.
Every close call and every near-catastrophe was answered in kind. If Gainesville's 7-6 lead at the break left you with the impression one team was significantly better than the other, consider removing those rose-colored (or jade-tinted, as the case may be) glasses.
When both teams sputtered to start the second half, what the game needed was a hero; someone to take control.
That's about the time Johnson took over.
Midway through the third quarter, he had 5 yards on two carries, including a 1-yard touchdown run in the second quarter.
His next carry went for a 37-yard score. His next went for 11 yards. His next went for 9. His next went for 27.
You get the point.
Over the course of the game's final 18 minutes, he carried 15 times for 187 yards and two more scores that broke the back, if not the will of the Trojans.
Not bad for a linebacker who had never registered a carry in a varsity game before Gainesville needed to ice a win against White County two weeks ago.
To run out the clock in that game, Gainesville coach Bruce Miller inserted the 6-foot-3, 235-pound Johnson to take the direct snap in a wildcat-style offense Johnson himself dubbed the "Gorrilla." The plan worked, as Johnson pounded out 76 yards and the game-clinching touchdown on nine fourth-quarter carries.
Miller had hoped to keep that little wrinkle in his offense hidden until Friday's game against North Hall. As it turned out, he didn't need to.
By Gainesville's last drive, everybody in the stadium and a good chunk of those listening on the radio and watching on TV could see what was coming, but there wasn't a thing anybody could do to stop it.
"Just super," Gainesville coach Bruce Miller said when asked to summarize the senior's performance. "To play as many plays as he did on both sides of the ball and not get tired; and he'll tell, he doesn't get tired."
Even so, North Hall fought back with heart befitting the reputation it's earned in the last 10 seasons under Bob Christmas. The Trojans gave themselves a chance to win when they cut the lead to seven with 5:30 left, but in the end, they simply had no answer for the best player on the field.
Johnson carried the ball on nine of the final 10 plays as the Red Elephants moved from their own 20 to inside the North Hall 10 and chewed up every last second left on the clock.
After watching these two go toe-to-toe, I'd be surprised - not shocked, but surprised — if there's not a rematch played back at The Brickyard on Nov. 5 in the Region 8-AAA championship game.
If and when that happens, there's every chance that one player won't be able to make such a difference. But the truth of this Friday night is that one player did.
Brent Holloway is the sports editor for The Times. Follow him at twitter.com/bholloway.