I don’t think UC Santa Barbara will upset Kansas in tonight’s season-opener in Allen Fieldhouse. The home-court advantage is much greater in the fieldhouse than most places — especially in home openers, in which KU has won 41 in a row. Plus, Kansas has greater depth of talent.

But I will say that this sort of experience imbalance fits the profile of a March Madness upset. Two players on the floor tonight best illustrate the challenge for a young, elite school trying to defeat an experienced mid-major with a star player, and the challenge the mid-major faces in trying to overcome a raw talent disparity.

UCSB senior Alan Williams, all 6-foot-8, 265 pounds of him, ranked 12th in the nation with 21.3 points per game and second with 11.5 rebounds.

Kansas freshman Cliff Alexander, all 6-8, 240 of him, ranked fourth per rivals.com among Class of 2014 recruits.

Both men have long wingspans — Williams 7-1-1/2, Alexander 7-3 — and Alexander is a more explosive jumper, a faster runner, blessed with better lateral quickness. Alexander can do certain things Williams never will be able to do because he has a more athletic body. Alexander can’t yet do many things Williams can, such as know how to make himself available in the post to receive passes for easy buckets, because he didn’t need to develop sophistication in his game to dominate. Properly sealing his man for an over-the-top pass is a reflex to Williams from any spot in the post. It’s something Alexander is learning on a daily basis at the big-man laboratory that on an annual basis is as good as any in the country. Williams knows how to draw fouls and avoid them. Alexander is learning how to do that.

Williams, who won’t play as difficult a schedule as Alexander, will produce more consistently. Alexander, coming off the bench tonight, will have help if he ever guards Williams. (Kansas likely will start with Jamari Traylor on him). During his time on the floor last season, Williams took 37.17 percent of his team’s shots, fifth-highest figure in the nation. So how does Kansas stop him tonight? The first step includes rattling the guards into throwing the ball away, even using full-court pressure at times.

“Williams is a great guy at getting angles,” Self said. “He scores before he catches. He’s a man down there. And he goes after the ball like a man. We haven’t had a man compete like he’ll compete against us, even in practice guarding each other, because he really gets after it.”

Nobody expects Alexander at this stage of his career to be as good at putting himself into easy scoring position as Williams, but nothing would make Alexander’s coach happier than if he duplicated the Gauchos All-American candidate in one area.

“You guys see him when the lights are on in the games,” Self said of Alexander. “I see him every day, and I will tell you this: I want him to be much more aggressive than what he’s been, but he is an aggressive-by-nature guy.”

Beyond Traylor and Alexander, Kansas has shot-blocker Hunter Mickelson and physical Landen Lucas are available to throw different looks at Williams.

Post defense ranks high among Self’s list of concerns about his shorter-than-usual roster and the Jayhawks are hit with a big test right off the bat, thanks to Williams.

“I wonder a lot about it and our length,” Self said. “He’s plenty good enough that if you play behind, he catches it and scores over you. If you front him, he’s great at sealing and they throw over and they look to do that, so we’re going to have to be pretty alert on the weak side, that’s for sure.”

UC Santa Barbara went 21-9 overall and 12-4 in the Big West last season, good for second place behind UC Irvine.

Michael Bryson, a 6-4, 201-pound junior, averaged 11.5 points a year ago and shot .417 from three-point range. Kyle Boswell, a 6-2 senior guard, averaged 10.4 points and shot .429 from three.

“Williams is their star, but Byron is a really good player, too, and he can move around the post, he’s a good three-point shooter, good athlete and they’re really quick on the perimeter,” Self said. “And they can stretch it the majority of the game at four spots, so it’ll be hard to trap the post and do things like that.”

After totaling 39 points, nine rebounds and eight blocked shots in an 83-64 rout of South Dakota State last December, the humble Williams showed he is as comfortable in front of a microphone as he is in the paint.