After a wild day that saw a few favorites escape by the skin of their teeth, the first day of the NCAA Tournament ended with three higher-seeded teams going home - two 5’s (Oklahoma and Cincinnati) and a 6 (Ohio State). They all had the same problem - they did not have an interior presence. Oklahoma and Ohio State played 4-out with an undersized center while Cincinnati had no starter above 6’7.

Ohio State started a conventional center in Amir Williams (6’11 250), but he was largely ineffective against Dayton, with 0 points in 18 minutes of action. They played four perimeter players around him, with LaQuinton Ross (6’8 220) at the 4. In the second half, Thad Matta pulled Williams and played Ross at the 5. As a result, Ohio State wasn’t any bigger than Dayton, an Atlantic-10 team that went 6’10 250 and 6’7 225 across the front-line.

Oklahoma was even smaller. The Sooners started Ryan Spangler (6’8 230) at center and played Cameron Clark (6’7 210) at power forward. In the Big 12, they won games by spreading out bigger teams, playing at a faster pace and outscoring them. It’s a style of play better suited for an underdog than a favorite. When you saw them on the court, OU didn’t look like the favorite. North Dakota State went 6’8 250 and 6’7 185 upfront - they were a little bigger.

Cincinnati was bigger and more athletic across their starting five than either OU or OSU, but they still had a massive hole at the center position. Mick Cronin’s team played five-out basketball, with three combo forwards - Justin Jackson (6’8 230), Titus Rubles (6’7 220) and Shaquille Thomas (6’7 205) - along their front line. All three were excellent athletes who played bigger than their size, but none could consistently score out of the post or protect the rim.

Not having big men who can play weakens a team on both sides of the ball. On offense, a team without a post presence can’t control the tempo of the game. When the other team is making a run, they can’t slow the game down, throw it inside and give themselves time to breath. On defense, a team that can’t protect the rim and clear the glass has a hard time putting anyone away, since the opposing team can always get easy points inside if their jumpers aren’t falling.

Just as important, a team without a 6’9+ player who can create their own shot is forgoing one of the easiest ways to score in a NCAA Tournament setting. For the most part, every team in the field of 68 has quality perimeter players. The frontcourt is what separates higher seeds from the rest of the pack - the supply of quality 6’9+ players is much more limited than the supply of quality 6’2+ ones. Most lower-seeded teams just don’t have the big men to compete.

That’s how a higher-seeded team can put away an upset bid before it even has a chance to get going. Everytime Delaware looked like they would make a run at Michigan State, the Spartans threw it inside to Adreian Payne (6’10 245). The Blue Hens, who didn’t start a center, had no answer for Payne, who scored 41 points on 15 shots. Delaware was one of the better lower-seeded teams in the NCAA Tournament - they could have upset a team without an NBA big man.

Of course, a lack of a big man isn’t the sole reason why Cincinnati, Ohio State and OU went down on Thursday. All three games came down to the final minutes, with Dayton winning by 1, Harvard winning by 4 and NDSU winning in OT. Anything can happen in the final minutes of an NCAA Tournament game. The key, from the perspective of the higher-seeded team, is not letting it get to that point. Delaware lost by 15; they never had a chance to steal it at the end.

When a high-major team downsizes, they are forfeiting the very advantage that comes with being in one of the bigger conferences. A small-ball game, by its nature, tends to be more high-variance, as both teams get more of their offense off jumpers and three-pointers. If you don’t have multiple NBA players on the perimeter, which neither OU, OSU or Cincinnati had, it’s hard to separate yourself from a quality lower-seeded team like Dayton, Harvard or NDSU.

The 5/12 pairings are one of the most common upsets because the differences in talent even out the deeper you go into the at-large pool. The difference between a 1 and a 5 seed is much greater than the difference between a 5 and a 9 or a 5 and a 12. At that point in the seedings, teams are being ranked as much on their schedules as anything else. When you play Summit League or Ivy League teams for two and a half months, it’s hard to have a big RPI or SOS.

And while a low-major team will almost never be able to find a 6’10+ athlete with NBA ability, they are usually able to scrape together a few 6’8 guys who know how to play. Harvard is hardly a big team, starting two 6’7 225 forwards upfront, but they have just enough size to make themselves a credible opponent, given the right match-up. Unfortunately for them, they face Michigan State in the second round and they have no one with a prayer of guarding Payne.

When you don’t have enough size to defend the post, you are forced to play on your opponent’s terms. Since Harvard can’t single cover Payne, Michigan State can throw it inside and live with whatever happens. Either Payne gets a clear look at the basket or he draws a double team and moves the ball back outside to one of the Spartans perimeter shooters. It’s all about balance - if Payne was playing with guards who couldn’t shoot or pass, he would be ineffective.

One of the most common misnomers about the NCAA Tournament is that it’s a “guard’s game.” While it is very hard to win games in March without quality backcourt play, it is just as hard to win them without quality play in the frontcourt. The best teams have good players at each of the five positions on the floor, which allows them to match-up with any opponent. A high seeded team without a big man is like a boxer with a weak chin - the upset is always a possibility.