March Madness Sweet 16 betting trends, stats and notes from the Action Network

Below are some of the highlights, but trust us, this only scratches the surface. For more, and we mean LOTS more, click here for the full Action Network betting primer!

Chalk Feast

Big Favorites Lead Way

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).

Cover City

Storring the Cash

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.

Up, Up and Away

The Alabama Rocket

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.

Undefeated Heel

Bama Next

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.

Feeling Blue

The Lower Seed

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.

Quiet on the Western Front

Is This The Year?

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.

Momentum Matters Sometimes

Don't Lose Early

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.

Big Cyclone

Tough Start

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.

Buyer Beware

Tighter, Later

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.

Top Chalk

History Coming?

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

Public's Revenge

Record Weekend

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.

Hard to believe, but this is just the beginning. There's tons more great stuff in Action Network's betting primer!