Tua Tagovailoa started. And Alabama couldn’t be stopped.

Tagovailoa picked up where he left off last year, throwing a TD pass on the Tide’s opening possession of the 2018 season. (It came — fittingly — a few plays after he was sacked.)

By night’s end, he accounted for two more scores in the Tide’s methodical 51-14 dismantling of Louisville.

While Nick Saban spent the offseason dodging questions about which potential All-American quarterback would start the game, Louisville coach Bobby Petrino had a different challenge — how to make the Cardinals go without Lamar Jackson.

Saban had no wrong answer. Petrino had no other Jackson.

Essentially, that was the difference Saturday night in Orlando.

This game wasn’t supposed to be close, and it wasn’t.

Credit No. 1 Alabama for taking care of business. Tuck this performance away when we start comparing resumes — and remember how the Big Ten’s ranked teams struggled mightily in Week 1. Nothing is given on Saturday. Just ask Penn State, which very nearly lost to Appalachian State at home. Or Michigan State, which had to rally past Utah State.

Louisville with Jackson wearing a hoodie on the sideline isn’t as dangerous as the Cardinals would have been with him wearing a helmet and running wild.

But Jawon Pass was a 4-star prospect, the No. 5-ranked dual-threat quarterback in the 2015 class. You know who was No. 4? A guy named Jalen Hurts.

Pass had a few moments. Alabama just had more. That narrative played out in a 4-play sequence early in the second quarter. Pass scrambled on 3rd-and-8 to pick up a first down. Three plays later, with Louisville threatening at Bama’s 26, he threw into the end zone. Deointe Thompson rotated over and intercepted the pass, ending the threat.

Six plays after that — aided by Tagovailoa’s 49-yard strike to freshman Jaylen Waddle — Najee Harris bullied his way into the end zone, pushing Bama’s lead to 21-0.

By that point, Tagovailoa was 9-of-12 for 170 yards. He had thrown for one TD and followed Damien Harris’ perfect lead block 9 yards for another score.

Hurts replaced him on the next drive. His first pass glanced off the fingertips of tight end Irv Smith. His second ball fell short and to the right of Jerry Jeudy, who was running a go route near the right sideline. Those two misses led to Alabama’s first punt.

Hurts’ second possession included his first two completions but ended with another punt.

Tagovailoa returned for Alabama’s final possession of the first half — and the result looked like Georgia all over again.

On 3rd-and-10 at Louisville’s 25 with 14 seconds left, Tagovailoa threw left — not quite as far this time — but his 25-yard strike found Jeudy in the back of the end zone.

Just like that, Alabama’s offense brought back to life.

Saban walked off the field at halftime ahead 28-0 but hardly thrilled. He predictably found all of Alabama’s faults, particularly with the defense.

The second half was more of the same.

Were the Tide perfect? Hardly. The Tide missed an extra point and a field goal. Pass often had too much time to throw, too much room to run. Alabama’s linebackers left gaps that the Cardinals occasionally took advantage of. The pass rush in large part was stymied. An unsportsmanlike penalty against Christian Miller extended a Louisville drive and led to the Cardinals’ first points.

Saban didn’t mention Ole Miss by name when he said they were fortunate Louisville didn’t capitalize on the Tide’s defensive miscues. But he knows all too well that Ole Miss has the athletes — and the quarterback — capable of taking advantage of those blemishes.

Football teams are a work in progress, never as dominant, as thorough in Week 1 as they will be in Week 13. Or that is the hope, anyway.

Saturday revealed two things: Saban made the right choice at quarterback, though that had been obvious for a while. And on a day other contenders struggled and some lost, Alabama’s performance was much more win-and-thrive than win-and-survive.