As the seconds ticked down on Monday night’s victory over the Chargers, Baltimore Ravens coach John Harbaugh wanted to remind his defense to block out the noise and distractions and not jump offside.

He repeatedly tapped his cupped hands to the sides of his head as if putting on imaginary earmuffs.

Funny, in the week leading up to the hyped-up Harbaugh Bowl — the third iteration of the NFL’s only brother-to-brother matchup of head coaches — the Ravens coach had to heed his own advice. He had to ignore all the outside chatter and focus on the task at hand.

“Yeah, absolutely, it was kind of earmuffs in that sense, and I know it was for Jim too,” said John Harbaugh, who improved to 3-0 in games against his younger brother. “Because in the end it’s meaningful, it matters. It’s such an incredible thing. I’m so proud of him. It’s an amazing thing to look back at where we are, from where we came.

“We had different paths, and we grew up in the same room. We’ve always lived our lives side by side. But that’s not what the game is about. The game is about the players.”

Despite the obvious love and respect the two have for each other, there was no brother-to-brother backing off, no ostensible sibling sympathy in Baltimore’s 30-23 victory. Both John and Jim — whose teams very easily could meet in the playoffs in a couple months — were fully invested in the moment.

That’s why the Ravens went for it three times on fourth down, succeeding on all three, including once from their 16. Neither coach was taking his foot off the gas.

“The overriding thing was who we were playing,” said John, 62, 15 months older than Jim. “You’ve just got to try to hang on to possessions as long as you can, because they’re so good. … Their offense is so challenging and so good, we just felt we were going to need it.”

As the game clock hit 0:00, photographers, camera operators and other media flooded from the four corners of the field to the midfield lightning bolt to capture the brotherly handshake. That was brief, with John and Jim exchanging a few friendly words and a quick hug before heading their separate ways.

Chargers coach Jim Harbaugh (right) greets brother John, coach of the Ravens, before their Monday night game.

(Ryan Sun / Associated Press)

If you didn’t know what happened in the game, didn’t know the final outcome, it would be hard to tell by the postgame media sessions which brother won and which lost. They were both subdued and chose their words carefully.

“It’s every week at this level, everybody pours an incredible amount of effort and everything they have into these games,” Jim said. “I was really pleased with our effort, valiant effort, and their side of the ball had valiant effort as well.”

Just as John has won all three games coaching against his brother — including a Super Bowl victory — quarterback Peyton Manning was 3-0 against his younger brother, Eli. And just as those ballyhooed matchups were excruciating for parents Archie and Olivia Manning, they are tortuous for Jack and Jackie Harbaugh.

The Harbaugh parents attended the first two games pitting their sons, but Monday — which happened to be their 63rd anniversary — they were in Florida, watching from the home of their daughter, Joanie, who is married to longtime college basketball coach Tom Crean.

Both brothers reached out to their parents before the game.

“I wished them a happy anniversary, and I know Jim did the same,” John said. “Jim and I texted before the game a little bit. Just so grateful for our parents. When you’re blessed enough to have parents who get along so well, love each other, have been married 63 years, it kind of gives you an idea how it’s supposed to work. That’s the gift they’ve given all three of us.

“I know they’re 100% happy and 100% disappointed at the same time. If you can imagine that, that’s how they feel right now.”

The Ravens improved to 8-4 with the win, giving them a better record than the 7-4 Chargers and a significant leg up on them in the race for the postseason. There was no gloating from John about that. He opened his press conference by calling his younger brother “the best coach in the National Football League with how hard they play and what they did.”

He added: “They’re going to win a lot more football games this year, and they’re going to be a major factor in the playoffs.”

Back when they were kids, sharing a bedroom and occasionally trading punches, the ultra-competitive brothers made an agreement. They divided their room in two.

“John came up with this thing where he put a piece of athletic tape across the floor of the room we shared,” Jim, then coach of the San Francisco 49ers, told the Los Angeles Times in 2011. “He proclaimed that I wasn’t allowed to come on his side of the tape, and he wasn’t allowed to come on my side.”

Jim agreed to the plan, only later to realize most of the prime items — a record player, radio, desk and alarm clock — were on his brother’s side of the room. Jim had the closet where they kept their clothes and the bedroom door on his side, yet John was allowed to use those as necessary.

“So the deal was the deal,” Jim said. “But there are those 10 or 12 defining moments in your life, and that was one of them. I learned a valuable lesson the hard way: You negotiate a good deal up front.”

As for the tale of the tape now? It’s more loving but still lopsided.