When the lights came back to the Superdome, America’s biggest sporting event had changed.

This was the story line that no one predicted, a dose of unexpected drama that no one wanted. Super Bowl XLVII stopped for nearly 35 minutes because of a power outage, and while the Baltimore Ravens tried to protect an enormous lead, the San Francisco 49ers somehow were recharged.

No, the lasting memory from this game will not be that John Harbaugh defeated his younger brother, Jim, or that Ravens linebacker Ray Lewis ended his career with a championship. It’ll be that Baltimore survived an unexplainable collapse — defeating the 49ers, 34-31 — by leaning on its most dependable presence, quarterback Joe Flacco.

“We don’t make anything easy,” said Flacco, who was named the Super Bowl’s most valuable player after his 287-yard passing performance.

Let it be said now — and more than that embraced — that Flacco is one of the game’s best. He was, anyway, during these playoffs — the most challenging and legacy-defining period in a player’s career.

This wasn’t a showcase game of a fifth-year player who simply rode his team’s wave to the Vince Lombardi trophy. Flacco improved his mechanics and response to pressure, and he was at his best during the postseason. Eleven touchdowns this postseason and zero interceptions. The only other quarterbacks to pass for that many touchdowns in a single postseason were Joe Montana and Kurt Warner.

Still, Flacco didn’t do this alone, but he became the face of the team that’s now the face of the NFL. Baltimore’s defense is still considered among the league’s most formidable units, and running back Ray Rice shook off a second-half fumble to help his team protect a lead that was dissolving by the minute.

Flacco is his team’s most recognizable survivor, and this is true now of his career. Drafted in the first round in 2008, he heard for years that he wasn’t among the league’s elite passers. The Ravens haven’t yet signed him to a contract extension, though it was assumed he would be back in Baltimore. Now, though, the team’s gamble has likely cost it money; even if few are willing to admit that Flacco is a top-tier quarterback, he almost certainly will be paid like it this offseason.

“Joe has been so huge for us all year and especially the postseason,” Ravens tight end Dennis Pitta said. “Nobody deserves this more than him in this organization.”

In this game, Flacco watched as San Francisco’s second-year quarterback, Colin Kaepernick, sidestepped his own stress and shortcomings, pushing his team to a remarkable comeback that’ll be discussed for years.

“They handled that better than we did,” John Harbaugh said of the 49ers. “The momentum turned, and they handled it well.”

When the electricity went off early in the third quarter — a Superdome spokesman apologized for the delay, but the league issued no reason for it — the 49ers trailed the Ravens by 22 points. Jacoby Jones began the second half with a 108-yard kickoff return for a touchdown. But by the time the fourth quarter began, Kaepernick and his team had chipped the lead to five. Then, as the minutes ticked away, to two.

Kaepernick in these playoffs has improved substantially in the second half, and no opposing lead seemed out of reach. Sunday night’s comeback was one for the ages, but history remembers the winners.

John Harbaugh, like his brother, gambled with his team’s fate this season, firing offensive coordinator and friend Cam Cameron in December and replaced him with Jim Caldwell, a calming presence whose attitude spread to his offense.

This was a contrast, of course, to Baltimore’s rowdy defense, whose ceremonial face this postseason was Lewis, although Sunday evening showed that the old man’s plan to retire is probably a timely one. Still, a team built for years on defense — this was its calling card, even as Flacco developed and mostly underachieved — somehow regained control after Kaepernick’s comeback. Its fourth-down stop deep in Baltimore’s territory all but sealed the Ravens’ win.

“I was sitting there thinking there’s no way, there’s no way we stop them here,” Flacco said.

John Harbaugh didn’t stop taking risks Sunday inside the Superdome. His decision to try a fake field goal backfired and looked worse after San Francisco’s comeback, and calling for punter Sam Koch to take a safety late in the fourth quarter, did spend a few extra seconds but also trimmed Baltimore’s lead to a field goal. The coach, like his quarterback, survived — and when the Harbaugh brothers met after the Ravens’ win, they hugged, though John Harbaugh said it was a difficult moment.

By the time Flacco was prepared for this stage, Baltimore’s defense was aging. It was no longer the dominant unit of the previous decade. Now the Ravens needed Flacco to step forward, into the spotlight and into a classification that many observers said was beyond his talents.

Late Sunday, under bright lights in a stadium that had gone dark and threatened to change Super Bowl history, silver streamers fell and colorful confetti was pumped from cannons. As it did, Flacco ran toward the middle of the field and teammates piled onto him, pulling him to the ground.

“He has taken a lot of criticism over his career for whatever reason,” Pitta said. “But we’ve always believed in him.”