And, watched by their parents from the Superdome stands, the brothers met on the centre of the pitch after the match to exchange a handshake.
"The meeting with Jim in the middle of the field was probably the most difficult thing I have ever been associated with in my life," said John Harbaugh afterwards
"I am proud of him."
The Ravens coach, who shared a bedroom with his brother until going off to college, had seen his team soar to a 28-6 lead on the first play of the second half when Jacoby Jones returned the kickoff 108 yards for a touchdown.
But after a 35-minute delay because of a power cut, Harbaugh had a feeling that the game was far from over.
"The way it was 28-6 and the lights went out with whatever happened, I just knew with Jim Harbaugh being on the other sideline and all of those years we have been together, that the game was going to be a dogfight right to the end," he said.
"Those guys were coming back. There is no greater competitor and no greater coach in the National Football League or in the world, as far as I am concerned, than Jim Harbaugh.
"The way that team played proves it. They showed it today, the way they battled back and fought right to the end. That is who he is and that is who they are. I could not be more proud of him and what he has done."
The 49ers coach paid tribute to his side's efforts in staging a dramatic late comeback at the Superdome.
"Our guys battled and they competed," he said.
"We got a spark and we weren't going to look back after that. We battled right to the brink of winning. It was a heck of a football game."
Joe Flacco was named most valuable player after completing 22 of 33 passes for 287 yards and three touchdowns to inspire the Ravens to their first Super Bowl win since 2000.
"We don't make anything easy," said Flacco, who has guided the Ravens to the playoffs in each of his five NFL seasons. "It was a hard-fought game on both sides.
"We gave the country a pretty good game to watch. Not to our liking necessarily but that's the way it goes sometimes and that's the way we do things."
Flacco is now a free agent, with the Ravens management insisting it will do whatever it can to keep him in Baltimore - but the player remained quiet on his future.
"I've never cared," Flacco said after the Super Bowl of his naysayers. "I don't ever want to feel like I'm in a position to (have to) defend myself. It's just not right."
The San Francisco 49ers lost in a Super Bowl final for the first time, having on all five previous appearances in the championship game.
Questions will likely be asked about how the side fell short, after failing to convert three times from the five-yard line with victory in sight.
"All I could think of was maybe running a different play but that is a player mentality," said Vernon Davis, the 49ers tight end.
"Greg Roman, he calls the shots, we have to go with it, we have to respect what's called. He believed in it, we believed in it, but it just didn't work," he added.
Three times Colin Kaepernick tried to reach receiver Michael Crabtree in the end-zone but failed.
Davis said he was surprised that on the fourth down, Crabtree, who had 109 yards on five catches and one touchdown, was again the intended target.
"A little surprised but it's coach's call," said Davis. "I guess they wanted to get the ball to Crabtree. It's tough for the coaches in that situation because if it works, you are a genius and if it doesn't you messed it up.
"It is a tough situation for the coaches."
But for Ray Lewis, the Ravens linebacker, the result meant his last game in the NFL finished with victory in the Super Bowl after a storied 17-season career.
"What better way to go out?" the 37-year-old said afterwards.
"It was an up-and-down roller-coaster with the injuries. Now, I get to ride off into the sunset with my second ring.
"For us to stand up like that ... to me, that was one of the most amazing goal-line stands I've been a part of in my career. What better way to do it than on the Super Bowl stage."
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