Don Fambrough, no spring chicken anymore, was not doing well. But through the trying times, he managed to keep his priorities straight.

He had to. It's a life's calling.

Battling a serious illness several years ago, the former University of Kansas football coach was strongly urged by doctors to head to Kansas City, Mo. — across state line — to get the proper treatment that might save his life.

"I'll die first," Fambrough snapped.

On the other side of the border, former Missouri basketball coach Norm Stewart was said to have stopped the bus in Kansas City, Mo., for team meals on the way to the KU-MU game in Lawrence, Kan., every year.

Putting a cent into the Kansas economy was feeding the enemy. He would have none of it.

This is the Border War in a nutshell — a deep-rooted hatred that's accepted and even celebrated when the two schools do battle on the playing field.

Kansas City, where thousands of Jayhawks and Tigers manage to co-exist, is ground zero for one of the most passionate rivalries in sports. Fitting then, that the biggest football game in the history of the Border War — Saturday's primetime clash between No. 2 Kansas (11-0) and No. 3 Missouri (10-1) — will be at Arrowhead Stadium, a split crowd that expects to be as loud as a jet.

It's setting up to be a glorious chapter in the history of the two schools. One team will be soaring in happiness when it's all done. The other will be crushed.

Of course, moments like this have defined the rivalry. Just think of the zaniness between these two schools over the years:

• The 1960 Jayhawks knocked off No. 1 Missouri, 23-7, in the season finale in Columbia, though it was later forfeited due to Kansas playing an ineligible player. Nevertheless, both schools now count it as a win, causing a disagreement in the all-time series (KU says 54-52-9 in its favor, MU says it's a 53-53-9 tie).
• A pint-sized running back for Kansas named Tony Sands ran the ball 58 times for 396 yards against Missouri on a blistery cold day in 1991. At one point in the second half, KU's offensive linemen started mocking the Mizzou defense, saying "You think this is going to be a pass? Nahhh!"
• Missouri beat a 2-10 Kansas team, 36-12, in the 2002 edition. Afterward, the goal posts were torn down — by the players.
• The Jayhawks currently are 14-1 in their last 15 games. That one loss? A 42-17 beatdown by the Tigers last year that ultimately denied Kansas a bowl bid.

Through all those landmark moments in the rivalry, the animosity grew steadily between the two fan bases. This week, it's about to explode.

Close to 80,000 fans are expected to be at Arrowhead on Saturday, with the lower level split 50-50 between KU and MU. On the field below, the Big 12 North title will be won, and national-championship aspirations will be both salvaged and ruined. A Heisman Trophy candidate will have another notch on his belt, be it Missouri quarterback Chase Daniel or Kansas quarterback Todd Reesing.

But with this rivalry, it's so much more than short-term accomplishments. It's historical relevance dating back to the 19th century — Bleeding Kansas, Quantrill's Raid. Eventually, the Civil War.

Don Fambrough — he's alive and well despite the stubborness — is no history teacher. But his deep hatred of Missouri has prompted (or forced) current Kansas coach Mark Mangino to have Fambrough give a passionate speech to the team on the eve of the annual Missouri game.

He'll exaggerate, fabricate and slip some truth in there occasionally. But he always, always makes sure the players know that this is no game.

It's a 150-year old war.

"They started the war," Fambrough will cry, "and eventually we're going to end it!"

Sadly, Kansas-Missouri may not be mentioned in the same breath as Ohio State-Michigan or Alabama-Auburn or Duke-North Carolina in the national scope. The passion and the hatred, to this day, remains college athletics' best-kept secret.

Jim Rogash / Getty Images The Week in Sports Pictures The nation grieved for those hurt, killed and affected by the Boston Marathon bombings. After one of the suspects was caught on Friday — following a day-long lockdown and manhunt — sports returned to Boston over the weekend.

But it's slowly starting to creep out.

At a Garth Brooks concert last week in Kansas City's new Sprint Center, the country music legend's bass player revealed a "Kansas Alum" shirt to the crowd of 17,000-plus when he was introduced before a song.

About half the arena loved it. The other half wanted him to eat a brick.

"It was the loudest cheering-versus-booing I have ever heard in my life," one fan said.

Off to the side, a grin escaped Brooks' face as he shook his head in disbelief.

Now he knew.

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