Kansas City’s fourth major sport heats up today.

It’s not a professional team like the Chiefs, Royals or Sporting Kansas City, but an event, or series of events.

“College basketball tournaments are a franchise to Kansas City,” said Kathy Nelson, president of the Kansas City Sports Commission. “It’s always been that way.”

Pretty much.

Look at what’s coming, and its origins.

The first of 31 NAIA Tournament games tips off at 9 a.m. today in Municipal Auditorium. College basketball’s oldest tournament started in Kansas City in 1937.

The Big 12 men’s basketball tournament starts at 6 p.m. in the Sprint Center. The conference tournament idea started in Kansas City as a holiday affair in 1946 and a holiday or postseason tournament has been in Kansas City in all but a handful of years ever since.

Next week, opening-round regional games for the 75th NCAA Tournament appropriately arrive at the Sprint Center. The first NCAA Tournament wasn’t played in Kansas City, but the second one was, and the event that would grow into March Madness took root here.

In all, 49 teams will play 46 tournament games over eight of the next 12 days.

But there are some changes this year.

The Big 12 women played elsewhere. For the first time, the Big 12 split up the men’s and women’s tournaments at different times and locations, which happens often in other conferences. The women wrapped up their tournament Monday as No. 1 Baylor defeated Iowa State before 8,662 at American Airlines Center in Dallas.

But the biggest change is the Big 12 lineup. Absent is the home-state team.

Mizzou opens play Thursday in the SEC Tournament in Nashville, Tenn. Replacing the Tigers and Texas A&M in the Big 12 are West Virginia and TCU, which are part of the schedule tonight at the Sprint Center.

“Last year, I was super excited about the tournament here,” said Bill Sosna, who grew up a Kansas fan, attended Missouri and reveled in the Tigers’ triumph in their final Big 12 men’s basketball tournament last March.

“This year, it just feels weird. It’s like some of the city is turned in a different direction.”

Unless the Tigers are assigned a spot in the NCAA second- and third-round games March 24 and 26 at the Sprint Center, Missouri will not have played a football or men’s basketball game in Kansas City this school year.

That seems odd to the most Missouri Tiger of ’em all.

“When we went to Kansas City for the tournament, we convinced ourselves that it was our tournament,” said Norm Stewart, the legendary Tigers coach who amassed 634 of his 731 career victories in 32 seasons at Missouri before stepping down in 1999.

And often the Tigers played like they owned Kemper Arena. Missouri won six of the 20 Big Eight postseason tournaments, more than any other school. Mizzou won it as a seventh seed. Twice.

“It was always a great trip for us,” Stewart said. “And it was a great run for our fans. They loved going to the tournament in Kansas City.”

The Tigers also loved their tangles with Kansas, wherever they occurred — another connection to Kansas City, with both schools’ large alumni and fan bases on both sides of the state line. But those games have been put on hold.

Missouri has expressed interest in continuing an athletic relationship. Kansas has not.

KU athletic director Sheahon Zenger reiterated the school’s feelings about the interruption of the series at a Tuesday panel discussion sponsored by the Centurions Leadership Program of the Greater Kansas City Chamber of Commerce.

“I can’t say when it could happen, but, no, not at the moment,” Zenger said of an athletic relationship with Missouri.

Missouri doesn’t figure to have much of a presence downtown during the Big 12 festivities. Duke’s On Grand, a bar at the corner of Truman Road and Grand with a view of the Sprint Center, has partnered with PowerMizzou.com for Missouri watch parties. But Duke’s might not serve many in Tiger stripes while the Big 12 balls are bouncing.

“But we’ll have the games on,” Duke’s managing partner Justin Quigley said.

Saturday and Sunday provide the best-case scenarios. If the Tigers reach the SEC semifinals, they would play Saturday at 2:30. The Big 12 title game that day is at 5 p.m.

And if Mizzou reaches Sunday’s title game, the Big 12 will have moved out and Duke’s would have the neighborhood to itself.

A Sprint Center sellout is expected for the Big 12, but a year ago the sellout sign went up a week before the tournament. As of Tuesday night, tickets were still available for this year’s games despite several reasons for high fan interest in the region.

Kansas and Kansas State shared the Big 12 championship. Iowa State, always with a substantial following, looks like an NCAA Tournament-bound team. Oklahoma State has the Big 12 player of the year in Marcus Smart, and Oklahoma is pointed toward the NCAA Tournament for the first time since the Blake Griffin days.

No Missouri meant one less school that would have snapped up its conference allotment of 1,100 tickets.

Last year, there was great anticipation of a matchup between the top two seeds, Kansas and Missouri. They would have been meeting for a third time after splitting the regular-season series in dramatic games.

But the Jayhawks lost in the semifinals and Missouri went on to win with MU fans chanting “S-E-C” in the final moments of the Tigers’ title-game victory over Baylor.

That day was a blast for the Tigers. Today, Missouri fans in Kansas City feel the absence.