SANTA CLARA, Calif. — This one will sting. And it should. The Detroit Lions belonged here. On this stage. The Super Bowl on the line. Tens of millions watching.

And hoping.

The Lions had won over this football-loving country. They were America’s team, and it would’ve been grand to see that carry over to Las Vegas, where they would’ve played the Kansas City Chiefs in Super Bowl 58, the last game of the season just like the first game.

Remember that game? That night?

When the Lions beat the Chiefs and reset the expectation?

CARLOS MONARREZ: Detroit Lions' NFC title game loss to San Francisco 49ers is franchise's worst meltdown

Well, it all led here, to the doorstep of the biggest stage in American sports, and for a half, it looked so promising. Heck, more than promising, it looked like the Lions were headed to the Super Bowl.

All they needed were a couple more plays. Plays they’ve made all season. Plays that got them here.

It fell apart slowly, then quickly, then definitively, and despite a late touchdown drive to make the score even more painfully close, the Lions couldn’t quite do it, and lost 34-31.

Maybe it was the moment, this is a young team playing on the big stage with everything on the line. Pressure has a way of disrupting execution, and the Lions learned that in the most painful of ways here at Levi’s Stadium in their first NFC title game in 32 years.

Or maybe they just ran out of magic. No, not pixie dust, just the magic of momentum, and the magic of finding a way to make a play after the other team just made bunches of them.  Because the Lions certainly belonged here. They weren’t overmatched or outclassed. This wasn’t like the 1991 season against Washington.

They just got beat, mostly because they got tight, at least a little, and couldn’t handle the shrinking margin for error.

A dropped pass. A dropped interception. A throw a little high. A missed chance to down a punt deep.

A missed sack.

A fumble.

None of them game killers on their own. But together? One after the other? Can’t get to the Super Bowl that way.

They know that now. Know what has to happen. What can’t happen.

Know that a slip in focus for even a moment has ripple effects, ripples that turn into tsunamis, that end seasons.

Dan Campbell predicted it. Not that it takes a soothsayer to see it. Or say it.

And no, he didn’t predict this loss. Just that it would look bad at some point, and that his team would have to find its way back.

That this is just how these games go. Rare is the blowout in conference title games. Adversity is coming. Was always coming.

Campbell’s instilled belief in this team, belief that they would find their way. And you could see it for a while. Boy, could you see it.

They took a 24-7 lead at halftime. They outmuscled San Francisco. Announced themselves.

Then the lapses began.

One lapse in focus led to another, and then another, and then momentum started making its own kind of luck for the 49ers, as momentum tends to do, like when Kindle Vildor couldn’t hold on to an interception.

Actually, he couldn’t get both hands on it, and it bounced off him, and into the diving arms of Brandon Aiyuk, 51 yards down the field. Two plays later, Cam Sutton had a chance to pick off a pass, and couldn’t.

On the next series, Jahmyr Gibbs fumbled at the Lions 24. San Francisco scored four plays later. The next series, Josh Reynolds dropped a third-down pass. Had he held on it would’ve been a first down.

Then on the punt, a glorious shot from Jack Fox that bounced almost straight up near the goal line and gave the Lions a chance to pin San Francisco deep but couldn’t avoid the touchback.

On it went. The game flipped. The 49ers scored 27 straight.

It was a long way from the start. And if they showed they weren’t quite ready for the end stage of an NFC title game?

They showed plenty in the beginning.

Blasting the 49ers’ defensive front off the line. A handoff to David Montgomery went for four yards. The next went for 10. And then, as they’ve done all season, Goff dropped back off the play action and hit LaPorta for 14.

Less than two minutes into the game and San Francisco didn’t know what was coming. Ben Johnson took advantage and called a reverse to Jameson Williams. He took the handoff, sprinted right, cut up field, cut back, slithered through the secondary, then escaped the last, desperate clutch of a defender grabbing his jersey.

He stumbled, kept his balance, and scored. And they were off. Until they weren’t. Until the pressure got heavier and the mistakes came. Again and again.

They’ll take them into the off-season, into the summer, into camp and into next season. It’ll hurt for a while, and it should. But this is a beginning.

This article originally appeared on Detroit Free Press: Detroit Lions will learn from their NFC championship game collapse