SANTA CLARA — It had all gone wrong for the 49ers in the first half of the NFC Championship Game.
They were being manhandled on offense and embarrassed on defense. Even the Niners’ special teams were abysmal.
The score at halftime was more than fair — the Lions went into the locker room up 24-7, riding a Honolulu Blue wave of momentum, one they and everyone watching thought would carry the franchise to its first Super Bowl appearance.
The challenge for the 49ers was crystal clear and daunting.
No, it was near-impossible.
Everything — absolutely everything — had to go right in the second half.
And then, somehow, someway, it did.
The Niners scored an unprecedented 27 unanswered second-half points to win 34-31 and advance to their eighth Super Bowl in franchise history, and the second in the last five years. They’ll play Kansas City in Las Vegas on Feb. 11.
This team’s dream, goal, and expectation of winning a title is still improbably alive.
It required guts, gumption, ruthless execution, and some help from the Lions to finalize.
It required the most incredible half of football you’ve ever seen.
Sports has become a quantified realm in the last two decades. And those who believe in numerical optimization will tell you that momentum isn’t real.
I wonder if those folks watched Sunday’s game.
The Lions could have won this game with seven minutes to play in the third quarter.
That’s when Detroit — the most aggressive team in the NFL — declined to kick a field goal that would have restored its 17-point lead. Instead, the Lions attempted to convert a fourth-and-2 from San Francisco’s 28-yard line.
And they made the play: Lions quarterback Jared Goff hit receiver Josh Reynolds in the hands, past the sticks.
But Reynolds dropped the ball.
The Lions could have won this game a minute later.
That’s when Lions cornerback Kindle Vildor had a ticket to the Super Bowl hit him directly in the face mask.
Brock Purdy, who had been woeful in the first half and shaky to start the second, despite that opening-drive field goal, had uncorked a deep pass down the middle of the field on the second play of the drive.
He overthrew his target Brandon Aiyuk on the play. He did not overthrow Vildor, though, who turned around and — plunk.
The ball popped into the air at the 10-yard line.
And Aiyuk, riding the momentum of his run, kept moving forward, catching the ball at the 7.
Three plays later, Aiyuk caught a touchdown. Game on.
Momentum — that unquantifiable and unstoppable force of belief — had flipped to San Francisco.
So obviously, on the next play from scrimmage, Niners safety Tashaun Gipson hit Detroit running back Jahmyr Gibbs and knocked the ball free. San Francisco ball.
A 21-yard Purdy scramble and 1-yard Christian McCaffrey touchdown later, the game was tied.
There was no stopping the Niners from there.
Purdy has always possessed the ability to scoot, but he was a reincarnation of Fran Tarkenton in the second half on Sunday. He had two big scrambles of 21 yards to set up that game-tying touchdown, and, eventually, the game-winning score.
With the Niners up 27-24 and at midfield with 4:40 to play in the game, Purdy took off on a third-and-4, running past two Lions pass rushers and a linebacker while keeping his eyes downfield. He finally tucked the away ball at the line of scrimmage, and with nothing but an open field in front of him, made another Lion miss en route to the new set of downs.
Two plays later, the Niners had turned a 17-point halftime deficit into a 10-point lead with 182 seconds to play.
The comeback matches the largest in NFC Championship Game history, a record previously held by the 2012 49ers, who came back from 17-0 at Atlanta.
And it was a comeback that would have been impossible without the play of the defense, which turned the worst half of football it played all season (280 yards allowed) into the finest. The Niners held Detroit to 87 yards as they rattled off their 27 straight points.
The Niners’ defensive line started to get pressure on Goff in the second half, moving the immobile quarterback around in the pocket. Goff, unbalanced and unsteadied, was 12-for-21 in the second half, missing eight of his final 10 throws in the meaningful portions of the game.
And the run defense, which was abysmal in the first half, found the right fits in the second: Detroit ran for 32 yards in the second half after going for 148 in the first.
There were two different color schemes of confetti for the cannons to shoot onto the Levi’s Stadium field at the end of the game.
Who could have blamed anyone if the blue-and-silver paper was stuffed at halftime?
But two quarters are not a game.
The 49ers looked the death of their season in the face last week, when they needed to score a touchdown on their final drive to beat the Green Bay Packers in the rain in the divisional round.
They didn’t flinch then. They were perfect when the moment called for nothing less.
When so many more moments called for that same level of play Sunday, they repeated the feat.
Attribute that to whatever you want — a deity, faith in one another, or the forever-nebulous “belief” — but no one can question that the 49ers have that powerful force on their sides.
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The theme for this 49ers season has been “unfinished business.” The 49ers knew coming into the season that they had the quality to avenge their NFC Championship Game loss to the Eagles last season and their Super Bowl loss in February 2020 to the Chiefs.
That game four years ago still stings. The Niners had a 10-point lead with a little over six minutes to play in the game.
They let it slip away. They lacked whatever they needed to win that game. They were on the wrong side of momentum that night in Miami.
And after the last two games — after one of the greatest wins in NFL history on Sunday — there is no doubt: When these Niners, talented and charmed, take on the Chiefs with it all on the line again, they’ll have what it takes to finish the job.