Baltimore Ravens Coach John Harbaugh walks off the field after his team defeated the Bengals on Sunday. (Nick Wass/AP)

There are no plans for the Harbaugh brothers to sit down together for a Thanksgiving meal Thursday. But their holiday will be all about family and football, two things they always have mixed seamlessly, and they seem perfectly content with that.

The NFL’s first matchup of brothers as opposing head coaches comes Thursday night in Baltimore, with John Harbaugh’s Ravens hosting Jim Harbaugh’s San Francisco 49ers. It is a meeting of equally rugged first-place teams that would be compelling no matter who was calling the shots from the sideline.

But it is inescapable, even for two football lifers with coaching tunnel vision, that the night’s biggest story line, by far, will be brother against brother.

“To say that’s not there, that you’re not thinking about it, I think probably wouldn’t be real,” John Harbaugh said. “I think it’s an amazing thing. It’s an historic thing. It’s very special.”

The Harbaughs’ story has been well chronicled since Jim left Stanford in January to jump to the NFL. The brothers shared a room as kids and still call themselves best friends who haven’t had a squabble for more than 20 years. They grew up around college football practice fields, tagging along with their father, Jack, a longtime coach who worked as an assistant to Bo Schembechler at Michigan and later won a then-Division I-AA national championship as Western Kentucky’s head coach.

San Francisco 49ers Coach Jim Harbaugh gave his team T-shirts with a family slogan last week. (Marcio Jose Sanchez/AP)

Jim was a standout college player as Schembechler’s quarterback for the Wolverines from 1984 to 1986, and had a 15-year NFL playing career. John, older by 15 months, was a defensive back at Miami University in Ohio but didn’t have NFL talent and began coaching for his father at Western Michigan at the age of 21. Jim followed them into coaching as well, and now the Harbaughs will be in the spotlight Thursday as pro football’s first family of X’s and O’s.

“I couldn’t be prouder of my family — prouder of my brother, prouder of my sister, prouder of my parents,” Jim Harbaugh said in a conference call with reporters.

The brothers had countless sports-related competitions as kids, with John Harbaugh recalling that they fashioned sleeveless T-shirts into makeshift Big Ten uniforms. They also used a tennis ball and a coat-hanger rim to play each other in basketball. But they last opposed one another in a formal athletic setting as teenagers on a baseball diamond in Ann Arbor, Mich.

“I’ve never rooted against him, really, ever,” John Harbaugh said. “We played against each other one time in baseball in high school, an American Legion team. My dad was actually coaching Jim’s team. And we won, 1-0. That’s the last time I remember. We were always on the same teams all the time. So it’s going to be a little different that way.”

Jim Harbaugh remembered that it was “a big game” for the team he and others formed after failing to make the cut for John’s Baskin-Robbins team.

“We almost pulled off the [upset],” he said. “That would have been right up there with ‘Rocky’ and the ‘Miracle on Ice.’ ”

Jack Harbaugh and his wife, Jackie, celebrate their 50th wedding anniversary Friday. They were in Baltimore for the Ravens’ triumph Sunday over the Cincinnati Bengals. They plan to be at the stadium Thursday before the game but intend to leave before kickoff and watch on television.

“We’ll be there, but we won’t be there for the game,” Jack Harbaugh said by telephone last week. “This is their opportunity, their moment. If we were in the stands, it would distract from the game and the teams.”

Jack Harbaugh said he thinks his sons have remained as close as ever, even with both in the NFL. “I don’t think their relationship has changed much at all,” he said. “I don’t know about the week of this game, but I know they communicate regularly. I don’t see any difference.”

The 49ers are scheduled to travel Wednesday to Baltimore and return home immediately after the game. The brothers’ only Thanksgiving get-together, they say, will be on the field at M&T Bank Stadium.

“It’s about football, really,” John Harbaugh said in a conference call early this week. “We wouldn’t have Thanksgiving together, anyway, if we were playing a normal game. But I’m sure both of our focus is going to be on the game and on our team. There’s no time for anything else.”

The Ravens, with a record of 7-3, are tied atop the AFC North with the Pittsburgh Steelers. The 49ers are 9-1, comfortably ahead in the NFC West and challenging the unbeaten Green Bay Packers for conference supremacy, transformed by Jim Harbaugh from a team that went 6-10 last season. The team had a saying used by the Harbaugh family — “Who’s got it better than us? Nobody.”—printed on T-shirts for its players. John Harbaugh said this week he wished he’d thought of that first.

John said the ticket-buying burden for the many family members coming to town for the game had fallen to him.

“I think all of the Harbaughs, the extended Harbaughs, will have a great time, one way or the other,” John said. “I think there will be one Harbaugh side that will be really happy and there will be another Harbaugh side that will be really, really disappointed. And then Mom and Dad will be torn. That’s kind of how I think it will go.”