Upsets are the biggest reason among many reasons why the first Thursday and Friday of the NCAA Tournament should be national holidays. Some of the upsets. we "all" have picked in our brackets, while others seem totally impossible to predict. It's that unpredictability of the tournament's first weekend that keeps us anxiously tuning in each year -- but that's not going to stop us from partaking in the fun of trying to predict the biggest surprises and upsets ahead of time, is it?

Let's turn to our nERD metric -- which is the amount of points a team would be expected to beat an average team by on a neutral court -- to look at six first-round matchups where the data points to closer games than the seedings might lead you to believe.

Want to get a huge leg up on your March Madness pool? Subscribe to numberFire and get instant access to power rankings, bracket picks, game simulators, and tons of awesome expert advice to help you make the right decision.

Even better, we're offering our subscriptions at $19 over the first month when you use the promo code BRACKET.

Miami (FL) (6) vs. Loyola (IL) (11)

After compiling a 28-5 record and finishing with a top 25 RPI, Loyola (Chicago) may be the most highly-regarded tournament entrant from a "one-bid" league this season. It's really no surprise to see them end up on this list no matter which opponent they drew in the bracket. But a draw against a Miami team that our models see as a pretty bad 6 seed makes Loyola a great upset pick.

nERD has the Rambers and 'Canes separated by just one point, and their adjusted offensive and defensive ratings, per Sports-Reference.com, are separated by just two points each. Loyola has won 17 of its last 18 games, powered by balanced inside-outside scoring and a top-25 defense, according to KenPom's adjusted defensive efficiency. Miami will be a tough test, but the Hurricanes are just 4-4 in their last eight games after starting the season 18-5.

Houston (6) vs. San Diego State (11)

San Diego State is one of the hottest teams in the country, having won nine in a row -- highlighted by a drubbing of a good Nevada team en route to winning the Mountain West Conference Tournament. Their Aztecs' foe, Houston, has been also been on a tear, winning 10 of its last 11 games entering the American Athletic Conference Tournament's championship game, where they came up just one point short against Cincinnati, who is a 2 seed.

No one's likely to feel confident betting against either of these teams given their recent play, but the value in this matchup seems to lie with San Diego State. The team's nERD ratings are just three points apart, and Houston has just a two-point edge in adjusted defensive rating. While Houston's been one of the more well-rounded teams in the country of late, it did not get an easy draw in the first round.

Clemson (5) vs. New Mexico State (12)

Clemson seemed likely to be an upset target before the bracket was released due to the attention given to senior star Donte Grantham's season-ending injury. The Tigers are just 7-6 without Grantham, though they did beat North Carolina in late January without him.

Clemson couldn't have been too excited to see 28-5 New Mexico State as its first-round opponent. The Aggies are a team that is just four points behind it in terms of nERD. Both teams are ranked inside Kenpom's top 15 of adjusted defensive efficiency. Given that low-scoring games are often the breeding grounds for higher variability and greater chances of upsets, this could be one to watch.

Though a word of caution before you get too excited about taking the Aggies -- New Mexico State is one of the poorest free throw shooting teams in the country, so they could have trouble putting away a game if they have a late lead.

Kentucky (5) vs. Davidson (12)

I know, I know -- Kentucky just won the SEC Tournament, and we're going to hear the "highly-talented freshmen starting to figure it out" narrative for the next several days. Of all the matchups on this list, this may be the least-mentioned upset pick because Kentucky seems to be peaking at the right time. But UK is only a month removed from a four-game losing streak in SEC play, and there have been legitimate questions about their consistency all season.

Davidson, meanwhile, has won eight of its last nine games, including an Atlantic 10 Tournament title. Coach Bob McKillop is well-known for leading high-powered offensive teams, and this year's Davidson squad is no exception as they rank 14th in adjusted offensive rating over. Davidson shoots well from all over the floor, and nERD has these teams separated by only 4.6 points. If Davidson's shooters get hot, this one could be of the scarcely-predicted upsets that makes March magical.

West Virginia (5) vs. Murray State (12)

West Virginia thrives on being one of the hardest teams in the country to play because of coach Bob Huggins' famed "Press Virginia" defense. But Murray State makes its opponents grind out long possessions on defense and holds its opposition to just over a 30% clip from three. If West Virginia is susceptible anywhere on D, it's the three-point line, where the Mountaineers are giving up 37% shooting to its opponents.

If it's a lower-scoring, slower-tempo game, one in which West Virginia finds itself trading twos for threes, this one could be close. nERD has West Virginia as a 6.7-point favorite on a neutral floor, so this one isn't quite as enticing as the others on the list, but it's still worth watching given the style elements at play and Murray State's current 13-game winning streak.

Arizona (4) vs. Buffalo (13)

This upset call also seems to ask readers to suspend a little disbelief, but nERD has these teams rated within seven points of each other, which is three points closer than any other 4/13 matchup in this year's field.

If karma were statistically measurable, I'd be able to recommend fading Arizona much more strongly after its alleged off-the-court improprieties. But with coach Sean Miller (at least for now) back on the sideline, the Wildcats rebounded in time to right the ship and win the Pac-12 Tournament. Still, given the relative weakness of the Pac-12 this season and the uncertainty surrounding Arizona's program right now, it wouldn't hurt to treat this uber-talented bunch with at least a shred of skepticism.

Buffalo has won eight of its last nine en route to a MAC Tournament title, and they boast top-50 adjusted offensive rating. Buffalo's offense will be up against an Arizona defense that often struggles to generate turnovers and ranks a mere 70th in defensive efficiency.