Whoever said you couldn’t teach an old dog new tricks was full of it.

Whether that’s true or not, Nick Saban showed Monday night that even though he might be considered an old dog, he still has plenty of new tricks.

Never before had Saban made a halftime substitution at the quarterback position, at least not in a national championship. The trick, he hoped, would jump-start an Alabama offense that was shut out at the break for just the second time in the last decade. Pull Jalen Hurts — the guy who led the Tide to consecutive national title games to start his career — and lose, and that move would be scrutinized until the cows come home.

Had Saban’s trick come up short, he would’ve been viewed as desperate. You could practically see the headlines declaring that Kirby Smart had passed his mentor. If pulling Hurts failed, Saban would have to answer questions about that move for an entire offseason and then some. It was the ultimate roll of the dice.

But that’s why he’s the greatest coach in college football history.

Saban couldn’t have known that true freshman Tua Tagovailoa would look like a modern version of Steve Young. After all, Tagovailoa had yet to play in a game in which Alabama led by less than 28 points. And to compare Georgia’s defense to Arkansas, Ole Miss, Tennessee or Vanderbilt — the only Power 5 defenses Tagovailoa faced in 2017 — would be like comparing Bear Bryant to a JV coach. How was this kid going to do what Hurts couldn’t?

Well, Saban got his answer in one throw. With one perfectly-executed go-route in overtime of the national championship, Tagovailoa cashed in his coach’s ultimate gamble. It was unlike anything we’ve ever seen before.

Nobody could’ve seen that coming from Saban. That kind of adjustment in that moment is the stuff of legend. Let’s not forget that just 10 days ago, Tagovailoa was quoted as saying he didn’t want to step on Hurts’ toes, and that he knew the job was his.

Saban didn’t worry about the politics of his decision. If Alabama won, he wouldn’t have to answer to any critics. If he didn’t find a way to rally his team from a double-digit deficit, the Tide’s redemption tour would’ve been a failure, by his own all-or-nothing standards.

Tagovailoa actually said in the postgame interview that Saban told him and Hurts that they would rotate in the second half. Saban would start Tagovailoa, though.

Yeah, I don’t buy that Tagovailoa was coming out of that game. If that was the plan, then Saban would’ve pulled the true freshman after Roquan Smith sacked him to force a three-and-out on Alabama’s first series of the second half.

Nah. Saban recognized that he needed someone who could attack Georgia’s secondary. Hurts, despite all his accolades, wasn’t that guy Monday night. Down double digits, Alabama couldn’t leave points on the board like it did when Hurts over-threw Calvin Ridley for what should’ve been an easy touchdown in the first half.

Alabama needed someone who could attack a Georgia secondary that had been vulnerable at times. Guys like Malkom Parrish were burned consistently. The Tide just needed someone who could make that be the difference.

It didn’t matter that Tagovailoa was a true freshman. And sure, Tagovailoa had his freshman moments. He inexplicably took a 16-yard sack that dropped Alabama all the way back to the 41-yard line before that game-winning score. He made an awful decision on an interception, too.

But who was it that Tagovailoa found streaking down the left side in overtime? That was fellow true freshman DeVonta Smith.

With all the talent Alabama has, it was two freshmen who delivered one of the most epic plays in college football history. And credit the Tide for giving true freshman Najee Harris a chance late in the game. The guy had 51 yards on his first 2 carries and actually finished as the Tide’s leading rusher while accomplished veterans Bo Scarbrough and Damien Harris watched from the sidelines.

In his previous life, true freshmen weren’t even on Saban’s 2-deep, much less throwing and scoring game-winning touchdowns in overtime of the national championship.

Credit: Matthew Emmons-USA TODAY Sports

This is an evolved Saban. This is the guy who cut down his team’s practice time ahead of the Sugar Bowl so that it would be fresh for Clemson. This is the guy who wanted his team to go out to the movies ahead of Monday night’s title game.

This isn’t the guy who is getting passed up by his former assistant. At least not yet.

Saban showed Monday night that the college football world still belongs to him until further notice. The Decade of Dominance isn’t over just because another SEC team finally looks to be a worthy competitor. Georgia is indeed that worthy competitor, and for all we know, Smart is going to continue to push Saban to new levels. He certainly did on Monday night.

Perhaps that’s why Saban displayed a rare emotional side at the conclusion of his sixth national championship. This wasn’t angry Saban who was frustrated that he got hit with the Gatorade cooler. This was relieved Saban, who did everything he possibly could’ve to pull out his most improbable accomplishment to date.

“I’ve never been happier in my life,” Saban told ESPN’s Tom Rinaldi in the postgame interview.

Saban has also never looked smarter than he did on Monday night. He might’ve moved into Bear Bryant’s 6-ring company, but Saban’s achievements are transcending generations in ways that even The Bear couldn’t do.

Age is just a number. That was never more evident than it was in Atlanta on Monday night. Who cares that Tagovailoa was still a couple years away from legally popping victory champagne, or that a 66-year-old head coach rolled the dice like he was a 21-year-old at the casino for the first time?

Saban is far from running out of tricks. Somehow, someway, his supply multiplied one more time.