March Madness has begun! On the tournment's opening day, only four out of 32 teams lost to lower-seeded foes but two of them were big: No. 2 seed Arizona and No. 4 seed Virginia both went down, busting millions of brackets.
Here is what to know going into the weekend of the NCAA Tournament, including the favorites and underdogs as well as key games:
HOW TO WATCH
Every game of the men's tournament will be aired -- here is a schedule -- either on CBS, TBS, TNT or TruTV and their digital platforms. CBS, which also has a handy schedule that includes announcing teams, will handle the Final Four and national title game this year.
The NCAA is streaming games via its March Madness Live option and CBS games are being streamed on Paramount+. Fans of longtime play-by-play announcer Jim Nantz should soak up every moment: It's his final NCAA Tournament.
TOP SEEDS
The top four seeds in the tournament are Alabama, Houston, Kansas, and Purdue. Each has had its share of headaches to set up what could be a chaotic tournament. Here is the latest from each region:
EAST REGION: The Boilermakers got a No. 1 seed for the fourth time, but Purdue could face potential hurdles in Memphis and surging Duke. Savvy veteran coach Tom Izzo and Michigan State are in the East, too, facing a first-round matchup with Southern Cal and coach Andy Enfield of Dunk City fame.
SOUTH REGION: Alabama, led by coach Nate Oats in a challenging season, is a No. 1 seed for the first time behind SEC player of the year Brandon Miller, who has armed security on hand after being the subject of threats. The Crimson Tide opened the tourney with an easy win. Potential hurdles could include Baylor or Missouri.
MIDWEST REGION: Houston got a top seed and won its opener but All-American Marcus Sasser is hobbled by a groin injury. Potential hurdles could include Penn State, which hammered Texas A&M behind eight 3-pointers and 27 points from Andrew Funk. Former Arizona coach Sean Miller has Xavier in the tourney, too, and held off Kennesaw State in its opener.
WEST REGION: Kansas is the top seed in a stacked region and the Jayhawks pulled away from Howard in their opener to advance to a tantalizing second-round matchup against Arkansas. Kansas is doing all this without coach Bill Self, who is recovering from a heart procedure on the eve of the tourney. No. 2 seed UCLA looked every bit a title contender in its opener. No. 5 seed Saint Mary's held off VCU in its opener.
SHINING MOMENTS
Princeton and the Paladins grabbed the spotlight early on opening day and Penn State's Andrew Funk said goodnight with a spectacular shooting display.
The Ivy League's Tigers used a late run to earn their first NCAA Tournament win in 25 years, ousting No. 2 seed Arizona, 59-55. By then, the Paladins were already celebrating Furman's first tourney appearance since 1980 with a win over No. 4 seed Virginia, 68-67, on a deep 3-pointer by JP Pegues with 2.4 seconds left.
Texas A&M had no answer for Penn State's stifling defense and 3-point acumen of Funk, who hit 8 of 10 from deep to help send the Aggies home. Kam Jones of Marquette had a stunning second-half scoring binge to lead the Golden Eagles to a win in their opener.
GAMES TO WATCH
No. 4 Tennessee (24-10) vs. No. 5 Duke (27-8), Saturday, 2:40 p.m. ET (CBS)
The Blue Devils have won 10 straight under first-year coach Jon Scheyer with Jeremy Roach matching his career-high with 23 points in each of his last two games. The Volunteers blew an 18-point lead and survived a challenge from Louisiana-Lafayette in the opening round.
No. 7 Missouri (25-9) vs. No. 15 Princeton (22-9), Saturday, 6:10 p.m. ET (TNT)
Princeton grabbed its first tourney win in 25 years by using a late 9-0 run to upset No. 2 seed Arizona. The other Tigers ended a six-game tournament skid with their first win in the Big Dance since beating Clemson in the first round in 2010.
No. 1 Houston (32-3) vs. No. 9 Auburn (21-12), Saturday, 7:10 p.m. ET (TBS)
The top-seeded Cougars could be without star guard Marcus Sasser, an All-American who appreared to have reinjured a groin in the opening round against Northern Kentucky. Either way, the Cougars will have the find a way to slow Johni Broome, who was unstoppable in the Tigers' opening win.
No. 2 Texas (27-8) vs. No. 10 Penn State (23-13), Saturday, 7:45 p.m. (CBS)
The Longhorns will have to hope Andrew Funk falls into some kind of, well, funk, for the Nittany Lions. His barrage of 3s helped Penn State earn its first NCAA Tournament win in 22 years. Texas, under interim coach Rodney Terry, routed Colgate in the first round.
GO DEEPER
Gun violence has cost lives and disrupted college sports all season, touching some of the top programs in college basketball, including Alabama. Coaches have been thrust into uncertain and unwelcome roles in trying to navigate the topic -- as well as the fallout from the Supreme Court decision to overturn Roe vs. Wade.
On a lighter note, if you feel you know March Madness pretty well, try this 25-question trivia quiz put together by AP.
PLAYERS TO WATCH
The NCAA Tournament is filled with great players and the AP All-America team is a good place to get familiar with the names. It's also an event where guys you've never heard of -- no offense, Drake -- can take a star turn. Guard play is always going to be important (see: Baylor, 2021 title winner) and there are some NBA prospects in the mix.
Bet on this, too: Some player -- maybe more than one -- will have a chance to join the mustachioed Doug Edert (remember Saint Peters' inspiring run last year?) and find a way to cash in on their celebrity.
BETTING GUIDE
Who's going to win the national championship? The betting favorites this week to reach the Final Four are Houston, Alabama, Purdue and either Kansas or UCLA, according to FanDuel Sportsbook.
MARCH MADNESS CALENDAR
Selection Sunday set the bracket matchup s for the First Four and first- and second-round games that stretch from Florida to California. Sweet 16 weekend will see games in New York City (East Region), Las Vegas (West), Kansas City, Missouri (Midwest), and Louisville, Kentucky (South).
Where is the Final Four? In Houston, on April 1, with the championship game on April 3. Basketball aficionados, take note: The women's NCAA Tournament will hold its Final Four in Dallas, a four-hour drive up the road from Houston.
Can't get enough March Madness? Well, there is talk about expanding the tournament despite a host of challenges. Enjoy the 68-team version for now!