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Nobody would have blamed La Salle's weary guys for leaving the Sprint Center, finding the nearest bed in the team hotel and laying down for a well-earned snooze.

Ole Miss star Marshall Henderson? He was hitting the town to celebrate.

The No. 12 seed Rebels knocked off fifth-seeded Wisconsin in the second round of the NCAA tournament on Friday night, shortly before the No. 13 seed Explorers joined them in the third round with a stunning victory over fourth-seeded Kansas State — the clear home-court favorite in KC.

"Obviously, it feels good to win, survive and advance," said Henderson, Ole Miss' flamboyant guard, who was captured in pictures posted on Twitter celebrating in the Power & Light District of bars and restaurants near the Sprint Center hours after the 57-46 victory over the Badgers.

"I'm just glad we won because I didn't shoot the ball well," said Henderson, who still managed to score 19 points despite going 6 for 21 from the field. "I'm glad I'm going to have a chance to redeem myself on Sunday."

That chance will come against La Salle.

The Explorers beat Boise State in a First Four game Wednesday night in Dayton, Ohio, caught a late flight to Kansas City and then sleepwalked through most of Thursday. But when they suited up Friday night, they had energy in their legs again, building an 18-point halftime lead.

Kansas State fought back, even taking the lead in the closing minutes, before Jerrell Wright hit three critical foul shots that allowed La Salle to escape with a 63-61 victory.

"From start to finish, we put our hearts out there on both ends," said the Explorers' Sam Mills, who scored 10 points. "On the offensive end, we shared the ball and gave each other open looks, and on the defensive end we just worked the whole game."

The two games in the West Region certainly provided some upset-style drama, while the evening games matching teams from the South Region went much closer to script.

Eighth-seeded North Carolina built a big first-half lead before holding off No. 9 seed Villanova 78-71, while top-seeded Kansas struggled to a 64-57 victory over No. 16 seed Western Kentucky.

Let the Roy Williams vs. Kansas story line resume.

"A North Carolina-Kansas game, everybody comes to play," said the Jayhawks' Elijah Johnson. "Roy is coming back, there's going to be a lot of fans pumped up, and we'll be pumped up."

Mississippi (27-8) sure was pumped up, rolling into Kansas City after an impressive run in the SEC tournament and keeping its momentum going against the Badgers.

Henderson missed 12 of his first 13 shots and was 0 for 6 from 3-point range when he finally connected for a long 3-pointer. Then he remained unusually businesslike while scoring the rest of his 19 points, helping Ole Miss win an NCAA tournament game for the first time in 12 years.

Afterward, Miami Heat star LeBron James tweeted, "That dude Henderson from Ole Miss got the greenest light in NBA history!" Henderson shot back on Twitter: "I (STINK) AND GET A LEBRON TWEET!!! HAHAHAHA I DONT WANNA HEAR NOBODY SAY NOTHIN, IVE MADE IT!!!"

That's precisely the kind of unfiltered chatter and irreverent attitude that Rebels fans have come to love, and of course, that opposing fans have grown to loathe.

"Listen, we've seen this show before," Ole Miss coach Andy Kennedy said. "We were getting him looks and he made some big ones. Once he makes one or two, feed Henderson."

La Salle (22-9) had its pick of people to feed in the first half against Kansas State, shooting nearly 60 percent from the field while building a 44-26 lead.

The Wildcats settled down in the second half, even taking a 61-60 lead. But they also went the final 4:54 without a field goal, allowing the Explorers — who were just 3 for 18 from the field in the second half themselves — to finish off the upset victory.

It was the first time La Salle has won two games in the NCAA tournament since 1955 — in fact, the school hadn't won two games in the previous 57 tournaments combined.

"We're not playing with house money. That's not at all the way we would ever think," La Salle coach John Giannini said. "We want to win every game we play. We never think, 'OK, we don't have to win that game.' That would be a ridiculous way for any coach or player to think."

The win certainly stunned a building full of Kansas State fans.

It stunned the Wildcats, too.

"It's the worst feeling in the world," said Rodney McGruder, their leading scorer. "It's the last time I'll play a game in the K-State uniform, and the last time I'll be on a team with some of the teammates I have now. It just hurts to go out the way we did."

Kansas (30-5) nearly endured an even worse feeling, trailing Western Kentucky 31-30 at the break and needing a series of foul shots from Ben McLemore and Naadir Tharpe in the closing seconds to avoid becoming the first No. 1 seed to lose to a 16 seed in the tournament's history.

Jeff Withey had 17 points to lead the Jayhawks, who became the first Division I school to win 30 games in four straight seasons, after Memphis was forced to vacate the 2008 season.

The Jayhawks will take on Williams, their former coach, who won his 700th game on Friday night when the Tar Heels (25-10) put away Villanova. Williams led the Jayhawks for 15 seasons and racked up 400 of those wins at the school about a 30-minute drive west in Lawrence, Kan.

"You know, I'm human. I wanted to get 700," Williams said. "I'd like to get 800, 900, 1,000, 1,500. I know that's not going to happen. But my focus wasn't on that, it really wasn't. It was trying to get number 25 and have this team stay and play in another game."