What we saw over the last four days at the 2018 NCAA men's basketball tournament was much more than madness.

Once we thought an indescribable moment occurred, another burst into the spotlight to amaze us further.

After we catch our breath for three days, March Madness returns Thursday with the start of the Sweet 16, where a variety of unexpected matchups take place.

There's no guarantee we'll experience the same amount of chaos in the second weekend of the tournament than we saw in the first weekend, but we're not counting it out after the bizarre, yet wonderful, start to the competition.

Bracket

South (Games played in Atlanta)

No. 5 Kentucky vs. No. 9 Kansas State

No. 7 Nevada vs. No. 11 Loyola-Chicago

West (Games played in Los Angeles)

No. 4 Gonzaga vs. No. 9 Florida State

No. 3 Michigan vs. No. 7 Texas A&M

East (Games played in Boston)

No. 1 Villanova vs. No. 5 West Virginia

No. 2 Purdue vs. No. 3 Texas Tech

Midwest (Games played in Omaha)

No. 1 Kansas vs. No. 5 Clemson

No. 2 Duke vs. No. 11 Syracuse

Sweet 16 Schedule

All Times ET. Bold indicates predicted winners.

Thursday, March 22

No. 7 Nevada vs. No. 11 Loyola-Chicago (7:07 p.m., CBS)

No. 3 Michigan vs. No. 7 Texas A&M (7:37 p.m., TBS)

No. 5 Kentucky vs. No. 9 Kansas State (9:37 p.m., CBS)

No. 4 Gonzaga vs. No. 9 Florida State (9:59 p.m., TBS)

Friday, March 23

No. 1 Kansas vs. No. 5 Clemson (7:07 p.m., CBS)

No. 1 Villanova vs. No. 5 West Virginia (7:27 p.m., TBS)

No. 2 Duke vs. No. 11 Syracuse (9:37 p.m., CBS)

No. 2 Purdue vs. No. 3 Texas Tech (9:57 p.m., TBS)

Kentucky Leads History-Making South Region

One week ago on Selection Sunday, no one knew if No. 5 Kentucky would even make the Sweet 16 with No. 4 Arizona in the same quadrant of the bracket.

After wins over No. 12 Davidson and No. 13 Buffalo, head coach John Calipari's Wildcats are the headliner in Atlanta, a city where they'll have a massive home-court advantage.

With Arizona and No. 1 overall seed Virginia out of the way thanks to upsets by Buffalo and No. 16 UMBC, the freshman-laden Wildcats have a real chance of advancing to the Final Four.

The Wildcats are part of the first-ever regional without a top-four seed, per the NCAA's David Worlock:

Kentucky faces an intriguing battle with No. 9 Kansas State in the Sweet 16, but the SEC team appears to have an advantage given how poorly head coach Bruce Weber's team played in its win over UMBC, as it shot 40.9 percent from the field and made a single three-point basket.

The other clash in Atlanta features No. 7 Nevada and No. 11 Loyola-Chicago, two battle-tested mid-major programs.

Both the Wolf Pack and Ramblers won their pair of opening games in dramatic fashion, as Nevada beat No. 10 Texas in overtime and overcame a 22-point deficit against No. 2 Cincinnati, while Loyola used two last-second shots to knock off No. 6 Miami and No. 3 Tennessee.

Not only will Nevada-Loyola be an intriguing contest, it serves as a mid-major showcase, as the champions of the Mountain West and Missouri Valley Conference fight for a spot in the Elite Eight with a potential matchup against a national powerhouse in Kentucky on the line.

Can Purdue Continue to Overcome Isaac Haas' Absence?

No. 2 Purdue proved in its second-round victory over No. 10 Butler that it's capable of thriving without center Isaac Haas.

The senior big man fractured his elbow in the first round against No. 15 Cal State Fullerton, and although being ruled out of the tournament, he tried to play Sunday.

CBS Sports' Allie LaForce reported the brace Haas had on his elbow wasn't approved by the NCAA:

With Haas looking on from the sideline, Purdue's role players made major contributions alongside veterans Carsen Edwards, Vincent Edwards and Dakota Mathias.

The most important player of the group was freshman Matt Haarms, who did well in place of Haas in the paint.

Despite losing one of their leaders, the Boilermakers carry plenty of confidence into the Sweet 16, with higher goals on their minds.

Guard P.J. Thompson noted the opening weekend of the Big Dance was only the start for Purdue, per Nathan Baird of the Journal & Courier.

"Our goal wasn't to get to the Sweet 16," Thompson said. "Obviously beating Butler and doing it in the fashion we did without Isaac (Haas) was huge. But when we wrote our goals down, at the end, it wasn't to get there."

Purdue's path to the Final Four is one of the toughest, as it faces No. 3 Texas Tech in the Sweet 16 before either No. 1 Villanova or No. 5 West Virginia awaits in the Elite Eight.

While the task won't be easy without Haas, the Boilermakers received a huge confidence boost Sunday with the play of Haarms.

With the young frontcourt player thriving, and the experienced core of backcourt players leading the way, the Boilermakers could shrug off Haas' absence and advance to the Final Four.

Follow Joe on Twitter, @JTansey90.

Statistics obtained from ESPN.com.