J.J. McCarthy's NFL debut, delayed by a year due to injury, began as a slow burn.

It finished in an absolute firestorm.

No one had ever done what McCarthy just did. He's the first player in NFL history to contribute to three touchdowns in the fourth quarter of his debut, according to insider Jordan Schultz.

Even more impressive, McCarthy did it to lead a comeback to a 27-24 win.

He started it off early in the fourth quarter with a 13-yard TD pass to Justin Jefferson.

MORE: 'Have a little faith': How Bills pulled off unbelievable comeback to stun Ravens

Then he hit Aaron Jones on a wheel route for a 27-yard passing touchdown.

Finally, McCarthy kept it himself on a read-option, ran over a defender and found the end zone on a 14-yard touchdown run.

He answered a lot of the doubters that were already swirling.

MORE: Jerry Jeudy refused to lateral on final play, instead conveniently hit his betting over

The Vikings scored just six points in the first half, including a last-ditch 59-yard field goal before the intermission from Will Reichard that very well could've been no points.

And so the Vikings are 1-0, and they've got more belief in their young QB than ever before.