March Madness Sweet 16 Betting Trends, Stats, Notes: Action Network Betting Primer

The NCAA Tournament started with underdogs, ended with favorites and saw only Kentucky and Baylor fall as top-3 seeds in the first two rounds. The betting public dominated, while first half overs and big chalk brought bettors to the bank.

We're here to answer tourney questions, dish out stats and facts, talk futures, coaches, Cinderella and more.

Welcome to the March Madness Sweet 16 edition of Action Network's betting primer.

All data, stats and trends are updated as of Thursday, March 28, 1 p.m. ET.

Even after underdogs won 12 games outright in the Round of 64, which was the most since 2001, favorites had their way in the early rounds of the NCAA Tournament.

• Favorites went 30-22 ATS, the best start for chalk since 2008.
• Double-digit favorites went 15-2 SU and 14-3 ATS in the early rounds — the best ATS start ever for big chalk.
• Even further, top-4 seeds went 26-4 SU and 21-9 ATS, also the best ATS start ever.
• Round 32 favorites went 15-1 SU and 11-5 ATS. Just the third time ever favorites went 15-1 SU or better (2009, 2019).

Let's start with Dan Hurley. His 11-3 ATS (79%) record is the highest ATS win percentage for a coach (min. 10 games) in the seeding era since 1979. Hurley is the only remaining coach in the field who has won a national championship.

Connecticut has covered eight straight NCAA Tournament games dating back to the start of their 2023 run. They are an astounding 24-6 ATS (80%) in their past 30 NCAA Tournament games since 2009, covering the spread by 7.2 PPG with a $100 bettor up $1,624.

In Connecticut's past six Sweet 16 trips, the program has six Elite Eights, five Final Fours and four championships.

The Alabama-North Carolina total is sitting at 173.5 across multiple books. All three of Alabama's NCAA Tournament games have made betting history this year.

Hubert Davis is 8-0 ATS in the NCAA Tournament as a head coach. He is just the third coach since seeding began in 1979 to start his coaching career 8-0 ATS or better in the tournament. Gary Williams started 9-0 ATS, while Andy Enfield started 10-0 ATS.

It's not often that Duke is facing a team where the Blue Devils are the lower seed. This will be the 15th time it's happened to Duke in the seeding era and it is 6-8 SU and 8-6 ATS in those games. But recently, it hasn't gone so well.

Duke is a 4-point underdog against Houston — they haven't closed as a 4-pt dog or higher since their 1994 National Title game loss vs. Arkansas.

Duke has lost six consecutive tournament games as the lower seed, losing five straight ATS in that spot. Its last win came back in 1994.

Since Arizona won the national title in 1997, no team west of Texas has won it all. Here are the teams left in the tournament that fit that criteria: Arizona, San Diego State and Gonzaga.

Since seeding began in 1978, every NCAA champion to play in a conference tournament made it to at least their conference semifinals (won at least one game). In that span, eight champions never actually had a conference tournament ('97 ARI, '95 UCLA, '89 MICH, '87 IU, '81 IU, '79 MSU, '78 UK, '77 MARQ). No eventual national champion has ever lost its first conference tournament game, either (h/t Stuckey).

If this trend holds true, here are some of the teams that won't win this year: Duke, Creighton, Tennessee, Clemson and Alabama.

Entering this year, in the 64-team era, there have been 38 teams to enter the tournament as a 1- or 2-seed that weren't ranked in the preseason AP poll. They have combined for zero Final Fours, averaging fewer than two wins per tournament (via KenPom).

This year, that is Iowa State. Not to mention …

Iowa State entered the season at 100-1 odds to win the national championship and is now a 2-seed in the NCAA Tournament. The Cyclones are the 11th top-2 seed to be 100-1 or higher entering the year since 2009. The previous 10 teams never made it to the Final Four.

When it comes to the later rounds, fade the movement. When the line moves two points or more from opening to closing after the Round of 64, those teams are 9-26 ATS since 2005.

When that team closes as a 2-point favorite or higher, they are 4-17 ATS. Track the line movement here on Action Network.

North Carolina and Connecticut are both popular betting picks against the spread for the public. If they close at 75% or higher for their spread bet percentage, they'd make this list.

Since 2005, only 13 teams have closed with at least 80% of the spread bets in any round of the NCAA Tournament. Those 13 teams are 2-11 ATS.

Biggest Public Sides in Sweet 16 or Later Since 2005

The old "fade the public" mantra had been a profitable strategy year-to-year during March Madness, but that all stopped in the early rounds of this tournament.

After the First Round and Round of 32, the betting public (51% of spread tickets or greater) is 38-13 ATS in the NCAA Tournament — the best public NCAA Tournament start in the Bet Labs database by a wide margin.

Here's a look at the BetMGM futures market, from opening to current lines to win it all:

What You Need To Know…

• Connecticut is still the favorite to win it all as it has been for the better part of the season — opening as co-favorites with Duke when odds came out about a year ago.
• UConn was the pre-tournament favorite this year. How have pre-tournament favorites performed in March Madness recently?
• The pre-tournament favorite has gone on to win it all nine times: 2018 Villanova, 2005, 2009, 2017 UNC, 2013 Louisville, 2012 Kentucky, 2007 Florida, 2001 Duke and 2000 Michigan State.

• The longshot to win it all is Clemson, which is 100-1 to win it all. Clemson opened the NCAA Tournament at 150-1 to win it all and opened the season at a 200-1 price.
• Of the 16 remaining teams, 12 saw their odds naturally take a decline since the start of the Big Dance, but Purdue, Iowa State, Creighton and Alabama have stayed at the same odds.
• The other two big stories are NC State and San Diego State. Back on March 11, the Wolfpack were 1,000-1 and they entered the tournament at 200-1. For the Aztecs, they hope its rinse and repeat. They are 80-1 right now. Last year, they opened at 80-1 and were 80-1 entering the NCAA Tournament.

What are the highest odds to win the title entering the NCAA Tournament since seeding began in 1978?

2014 Connecticut at 100-1 odds. Who can match that still this year:

Only three other teams listed above 20-1 odds entering March Madness have won the title in that same time frame: 1985 Villanova (35-1), 2011 Connecticut (25-1) and 1983 NC State (25-1).

That would include nine teams still dancing in 2024:

In program history, Gonzaga is 19-10 ATS when seeded outside the top four — they are currently a 5-seed in the 2024 tournament. In terms of the line this week, Gonzaga hasn't closed above a 4-point 'dog in the tournament since 2014 and has only done so six times under Mark Few. The Bulldogs are 0-6 SU in those games.

The over is 40-25-1 in Few’s 66 total NCAA Tournament games coached, including 28-14 in the Round of 32 or later.

Teams that have won exactly two in a row SU entering the Sweet 16 — losing their last game entering the tournament — facing a team on a longer winning streak are just 10-23-2 ATS in the round, failing to cover the spread by 4.5 PPG.

Matt Painter against the spread in the NCAA Tournament:

• 20-7 ATS in Round 32 and 64
• 1-6 ATS in Sweet 16 or later.

Connecticut has played 21 NCAA Tournament games in Massachusetts, New York, New Jersey or Connecticut. The Huskies are 17-4 SU and 14-7 ATS in those games, including 8-1 SU/ATS since 2014.

Rick Barnes is 4-16 ATS in the NCAA Tournament since 2010 — the least profitable coach ATS of 298 head coaches. When Barnes is an underdog or listed as a favorite of under 10 points, his teams are 6-19 ATS in their past 25 tourney games, including 1-14 ATS since 2010.

When Barnes is favored for the full game in the NCAA Tournament, he is also 4-11-1 against the second-half spread in that game, the second-worst 2H ATS record as a favorite in the tournament since 2011 (ahead of only John Calipari).

Tennessee has never made a Final Four. The Volunteers have had their struggles as a top-seed in the Sweet 16.

Tennessee as Top-4 Seed in NCAA Tournament

• 2023 — Sweet 16
• 2022 — Round of 32
• 2019 — Sweet 16
• 2018 — Round of 32
• 2008 — Sweet 16
• 2006 — Round of 32
• 2000 — Sweet 16
• 1999 — Round of 32
• 1981 — Round of 32

This is the 10th time Tennessee is a top-4 seed in the NCAA Tournament.

In its previous nine trips, the Volunteers have been upset by a lower seed eight times (seven straight trips). The Volunteers have six Sweet 16s and no Elite Eights as a top-four seed, and have never made the Final Four.

When Tennessee is both a seed favorite AND a betting favorite in the NCAA Tournament, it is 9-19-1 ATS, including 3-9 ATS under Barnes.

Teams love to beat Duke, but what they do after beating Duke sometimes is the question. Since 2012, teams are 2-7 SU and ATS the round after beating Duke in the tournament and 3-10 SU in the past 15 years.

Duke entered the NCAA Tournament at 30-1 odds — the fifth time since 1979 they’ve entered at 30-1 or higher. They’ve never advanced past the Sweet 16 in the previous four trips.

Of all the teams left in the tournament, Duke stands alone for unders this year, going 20-11-1, including 2-0 in March Madness. The Blue Devils are 13-3 to the under in their past 16 games. They've gone under the total in their past four NCAA Tournament games.

Recently, Iowa State games have been streaking to the under — going 12-4 to the under in their past 16 games.

Alabama (24-9), Illinois (24-9) and Purdue (21-11) are the top teams to the over still left in the NCAA Tournament.

Additionally, the Crimson Tide are 15-4 to the over in their past 19 games and Illinois is 23-4 to the over in its past 27 games.

Over the past three seasons, Houston and Purdue have dominated first halves against the spread.

Houston coach Kelvin Sampson has also dominated second halves. With the Cougars, he is 14-4-1 SU and 13-6 ATS in the second halves of games in the NCAA Tournament.

On the other side of the spectrum, the worst 1H ATS record over the past three seasons (of coaches still in the field) belongs to Brad Underwood and Illinois (39-55-1 1H ATS).

Between 2012 and 2021, Greg McDermott and Creighton were 1-9-1 against the second-half spread in the NCAA Tournament. Since the start of the 2022 dance, Creighton is 7-1 ATS in the second half — complete turnaround.

Aside from Dan Hurley, Marquette coach Shaka Smart is the most profitable coach ATS over the past two seasons among coaches still in this NCAA Tournament. Smart is 42-25-1 ATS, fifth-best of 344 head coaches over that span. Smart's best two-year ATS stretch of his coaching career.

The Wolfpack are on a heck of a run, winning seven games in 12 days to get to the Sweet 16. They joined 2011 Connecticut in winning a conference tournament with five wins in five days. 2011 UConn then went on a run, going 6-0 SU, 5-1 ATS in the NCAA Tournament and winning it all.

Double-digit favorites in the Sweet 16 have historically seen an edge to the under in their games, going 20-11-1 since 1995, including 14-5-1 to the under since 2000.

After UNC’s sweep in North Carolina last weekend to head to the Sweet 16, the Tar Heels are 36-2 straight up and 26-11-1 ATS when playing in the state of North Carolina in the NCAA Tournament.

Since 1985, UNC has played in NC in the R64/R32 10 times. In their previous nine such tournaments, they won the Sweet 16 game directly after the “homestand.”

A good note if the Tide make the Elite 8. Alabama coach Nate Oats is 20-10-3 against the spread when coaching games on two days of rest or less, including 11-4 ATS in the SEC and NCAA Tournaments.

Double-Digit Seeds vs. Non-Double-Digit Seeds in Sweet 16: 8-3 ATS since 2017 and 13-5-1 ATS since 2012.

In the past three NCAA Tournaments, the ACC is 29-11 against the spread — their $1,530 profit is the best of any conference.

In this year's tournament, the ACC is 8-0 SU and 7-1 ATS, best of any conference.

This hasn't been the Big Ten or SEC's weekend recently. They are a combined 7-20-3 ATS in the Sweet 16 and Elite 8 since the 2016 tournament — excluding games in which the conferences faced off against each other. That is Alabama, Illinois, Purdue and Tennessee this weekend.

With Illinois and Purdue left in the field, the Big Ten's last hope is down to two. The conference hasn't won a title since Michigan State won it all back in 2000.

There are 16 head coaches left in the NCAA Tournament. Let's dive into a matrix of some ATS angles for these coaches with a Sweet 16 game on extended rest followed by a potential Elite 8 game on shorter rest on the horizon.

Let's take a look at three NCAA Tournament PRO Systems. Click each system for matches, bets and detailed profitability charts.

Notes: The old notion, "Fade The Public." This system targets under-bet teams in high-bet games. For this, we are using 1.1X daily bet average. If you have Bet Labs, increase that DB-AVG for smaller sample, higher ROI matches. Current matches: Alabama and Creighton.

Notes: Free-throw shooting in the tournament is key. This system targets the better shooting teams vs. the teams shooting under 75%. This system is 15-7 ATS in 2024 and 52-25-1 ATS since 2022. Current matches: Clemson and Creighton.

Notes: This system targets undervalued teams coming off a good defensive performance. The system is 49-20 ATS in the Sweet 16 and Elite 8. Current matches: San Diego State and Duke.

Notes: In the Sweet 16, teams coming off hot shooting performances facing teams that aren't have been a good fade overall. Current matches: Arizona, Illinois and Marquette.

Notes: Historically, being a hot ATS team hasn't gone well for teams later in the NCAA Tournament. In First Four and First Round, the system is .500, after that, it targets these worse ATS teams. Current matches: San Diego State and NC State.

Notes: This system is targeting underdogs who are coming off good defensive performances. The system works throughout March Madness, but is better later in the tournament. Current matches: San Diego State and Duke.

Let's take a live look at the biggest line movements for the Sweet 16 so far.

• Illinois 1-pt move: +2.5 to +1.5 vs. Iowa State
• Purdue 1-pt move: -4.5 to -5.5 vs. Gonzaga
• North Carolina 1-pt move: -3.5 to -4.5 vs. Alabama
• Connecticut 1-pt move: -10.5 to -11.5 vs. SDST
• Tennessee 1-pt move: -2 to -3 vs. Creighton

• Arizona-Clemson 2-pt move: 150.5 to 152.5
• Marquette-NC State 1-pt move: 150.5 to 151.5
• Tennessee-Creighton 1-pt move: 143 to 144

• None so far

The Connecticut Huskies won the National Championship last year, were the betting favorites entering this year's tournament with a chance to repeat and are still the favorites entering the Sweet 16.

Since 1976, 2024 UConn was the seventh team to be favored to repeat entering the following tournament. The last was Florida in 2007, who completed the task and repeated. Of the previous six teams, 2007 Florida and 1992 Duke are the only two to go back-to-back.

How has the betting favorite entering the tournament performed in the Sweet 16?

Houston lost to Miami last year.

Gonzaga lost to Arkansas the year prior.

Prior to those two losses, the previous 10 pre-tournament favorites advanced to the Elite Eight.

Pre-Tournament Favorite Loses in Sweet 16 or Earlier

• 2023: Houston: +550 (S16)
• 2022: Gonzaga: +300 (S16)
• 2010: Kansas +200 (R32)
• 2004: Kentucky +350 (R32)
• 1994: UNC +600 (R32)
• 1990: Oklahoma +250 (R32)

North Carolina is the unpopular 1 seed. They were 30-1 to win the title entering the season and 13-1 entering the tournament.

Since 2009, UNC is the 12th No. 1 seed to open the season at 30-1 odds or higher. None of the previous 11 teams won the National Title. 2017 Gonzaga is the only one to even make the Final Four.

Since 1979, UNC is the 23rd No. 1 seed to enter the tournament at 10-1 odds or higher — 2015 Duke is the only one to win the title, though six made the Final Four. 17 No. 1 seeds have entered the tournament at above 10-1 odds — three made the Final Four (2018 Kansas, 1984 Kentucky, 1997 Minnesota) and none made the championship game.

Over the past five NCAA Tournaments (since 2018), the most profitable round for underdogs is the Sweet 16 (24-16 ATS). Underdogs in the Sweet 16 and Elite 8 in that span are 35-24-1 ATS. They are one game over .500 ATS in all other rounds combined.

A 5-seed has never won it all. A 4-seed or higher has won five times (all since 1985). A 3-seed or higher has won six times since 1990 (23 UConn, 14 UConn, 11 UConn, 06 Florida, 03 Syracuse, 97 Arizona).

1: 26
2: 7
3: 5
4: 2
6: 2
7: 1
8: 1

Houston has played seven NCAA Tournament games in the state of Texas and is 6-1 SU, losing its last such game in the 2022 Elite 8 vs. Villanova.

Houston will be the fifth No. 1 seed to play the Sweet 16 in its home state: 2024 Houston, 2005 Illinois, 2003 Texas, 2000 Michigan State and 1983 St. John’s.

The only team to lose its Sweet 16 game was St. John’s. The other three made the Final Four with just 2000 Michigan State winning it all.

Heading into the Sweet 16, here are the biggest upsets in the tournament and the betting records set throughout the years …

➤In the 1995 tourney, the Texas Longhorns, behind coach Tommy Penders, were averaging almost 93 points per game and had back-to-back games with a total above 170. They faced Oregon in the First Round and won, then the total got a little higher when they faced an even higher-scoring team in Maryland, a game in which the Longhorns lost by 14. Both games went under the total.

➤The story of this over/under tale is Princeton's defense, which was No. 1 in the country in 1995-96 and allowing under 52 points per game. As a 13-seed in the First Round, the Tigers beat 4-seed UCLA, 43-41, and held the Bruins to 38.5% shooting (Princeton shot 37% and won). Then in the Round of 32, the total closed at 108 vs. Mississippi State, which beat Princeton, 63-41, barely staying under the total.

Easiest Bets Won in NCAA Tournament Since 1978: