SANTA CLARA — The postseason of living dangerously continued for the 49ers on Sunday.
The 49ers looked helpless for the first 30 minutes.
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After that, they looked nearly unstoppable.
The 49ers picked it up in every area — just as they did a week earlier — and Detroit Lions coach Dan Campbell made a couple of decisions that completely backfired.
The 49ers rallied from a 17-point halftime deficit to pull out a stranger-than-fiction 34-31 victory over the Lions in the NFC Championship Game, propelling the franchise to its eighth trip to the Super Bowl.
The 49ers will meet the Kansas City Chiefs in a rematch of Super Bowl LIV on Sunday, Feb. 11, in Las Vegas. The Chiefs advanced with a 17-10 victory over the Baltimore Ravens in the AFC Championship Game on Sunday.
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The 49ers trailed 24-7 at halftime at Levi’s Stadium and were getting steamrolled in every facet of the game.
For history buffs, however, there was some hope for the 49ers.
These franchises met in a 1957 playoff game long before any of these combatants were around. On that day, the 49ers led 24-7 at halftime. As the story goes, the Lions could hear their opponent celebrating on the other side of the thin walls in the locker room at Kezar Stadium.
The Lions roared back for a 31-27 victory. One week later, Detroit beat the Cleveland Browns in the NFL championship game. The Lions have not won another league title since that season.
Here are the takeaways from the 49ers’ scintillating victory:
Purdy, offense bounce back
Quarterback Brock Purdy and the 49ers’ offense had their worst showings of the season early in their two playoff games.
They got away with their issues in the divisional playoff round. But could they survive another poor first-half showing on Sunday against the Lions?
The answer was . . . yes.
The 49ers' offense got going in the second half, putting up 17 points in the third quarter to pull even.
They managed to make up for an abysmal first half of play with a strong second half with Purdy leading the way with his arm and his legs.
Christian McCaffrey scored on a 1-yard run late in the third quarter to pull the 49ers even at 24-24, then backup running back Elijah Mitchell gave the 49ers a 10-point cushion with his 3-yard touchdown run in the closing minutes.
There was one turnover in the first half, and that resulted in a quick touchdown for the Lions.
Purdy felt some pressure up the middle as Detroit defensive lineman Josh Paschal pushed the pocket against 49ers right guard Jon Feliciano. Paschal hit Purdy’s hand as the was throwing and the ball fluttered toward Deebo Samuel in triple coverage, where linebacker Malcolm Rodriguez made the interception.
Five plays later, Gibbs made 49ers safety Tashaun Gipson miss near the line of scrimmage, cut back and took it in on a 15-yard touchdown run to give the Lions a 21-7 lead.
The 49ers battled all the way back to take the lead, 27-24, early in the fourth quarter on Jake Moody’s 33-yard field goal.
Purdy finished the win completing 20 of his 31 pass attempts for 267 yards, one touchdown, one interception and a 89.0 passer rating, along with 48 yards on five rushing attempts
49ers make the defensive stops
The Detroit Lions’ offense took the fight to the 49ers.
From the outset of the game, Detroit was clearly faster, more aggressive, more physical . . . more everything.
But Lions coach Campbell might have gotten a little too aggressive.
The 49ers came up with stops on two critical fourth downs to enable major shifts in momentum. The Lions passed up opportunities for 45- and 48-yard field goals.
Detroit’s first fourth-down attempt failed when Lions receiver Josh Reynolds had a drop. The 49ers marched down the field to pull within 24-17 with 5:17 remaining in the third quarter.
The next time Campbell opted to go for it, he passed up an opportunity to tie the score midway through the fourth quarter.
Purdy and the offense took it from here to extend the lead to 10 points with 3:02 remaining.
That’s not exactly how this game began for the 49ers.
The defense looked miserable at the beginning of the game.
It took the Lions just four plays to get into the end zone, as speedy second-year receiver Jameson Williams scored on a 42-yard touchdown run through a slow-footed 49ers’ defense.
Defensive coordinator Steve Wilks had no answers for a Lions offense that routinely ripped off big yardage on the ground or through the air. Wilks was likely to take the brunt of the criticism if that continued for the 49ers.
When the 49ers fell behind 14-0 late in the first quarter, it was not over. But there was not a lot of hope for a team that figured to be able to score some points but showed no ability to slow down the Lions.
Big comebacks have not exactly been commonplace for the 49ers over the past seven seasons, as the 49ers had a 2-29 record when behind by two touchdowns or more. Their last such victory was Week 18 of 2021, when the team rallied from a 17-point deficit to defeat the Los Angeles Rams and earn a spot in the playoffs.
On the Lions’ final drive before the end of the first half Sunday, they picked up a third-and-12 on Gibbs’ 13-yard run and a third-and-18 on Jared Goff’s 23-yard strike to Amon-Ra St. Brown.
Those plays set up Michael Badgley’s short field goal that gave Detroit a 24-7 lead at halftime.
49ers finish the job at home
After trips to the NFC Championship Game the past two seasons, the 49ers’ road back was a long one.
The 49ers’ goal from the start of their offseason program was to make sure if they again advanced this deep into the postseason, they would not have to step on a plane to play.
Everything lined up for the 49ers this time around with the No. 1 seed in the NFC and come-from-behind victory over the Green Bay Packers in the divisional round.
And the 49ers took care of business against the third-seeded Lions to advance to the organization’s eighth Super Bowl in franchise history.
Their previous NFC Championship Game losses came at the Los Angeles Rams and in Philadelphia against the Eagles. The 49ers got off to slow starts in both of those seasons to prevent them from earning home-field advantage in the postseason.
This time, the 49ers wrapped up the No. 1 seed before the final week of the regular season.
The Lions were 8-2 at home this season, including victories in the playoffs when they never trailed. Detroit’s season ends with them holding a 3-3 record while playing on natural grass surfaces.
Meanwhile, with their victory over the Lions, the 49ers improved to 6-0 all-time at Levi’s Stadium in the postseason.
Their goal was to play at home with a trip to Super Bowl LVIII on the line, and the 49ers did not let this opportunity to slip away.