The first full day of the NCAA Tournament delivered chaos. Three double-digit seeds won outright, and favorites failed to cover in the majority of games — a brutal day for anyone who backed the chalk. The cover probability charts told the story all day long — Wisconsin was a 10.5-point favorite, but the model-estimated cover odds cratered from above 75% to nearly zero as High Point stormed back for one of the day's wildest finishes, an 83-82 upset that saw the Badgers' win probability plummet from 94% to under 2% in the final minutes. VCU's takedown of North Carolina was equally dramatic on the charts: UNC's cover probability peaked near 98% midway through the second half before the Rams ripped off a furious rally, forced overtime, and pulled away for the 82-78 win.
Upsets weren't limited to the underdogs with momentum. Texas controlled BYU from start to finish as an 11-seed, Saint Louis demolished Georgia by 25 as a 9-seed, and TCU erased a 15-point halftime deficit to stun Ohio State. On the chalk side, the 1-seeds survived but the margins told different stories — Duke needed every second to hold off 16-seed Siena 71-65 (nowhere near covering 28.5), while Michigan rolled Howard 101-80 but still fell short of a 30.5-point spread. It was a day where the favorites won games but the books won the covers.
TCU 66, Ohio State 64 — TCU pulled off a remarkable comeback after trailing 24-39 at halftime. Ohio State's win probability peaked at 88% as the Horned Frogs looked completely outmatched, with TCU shooting poorly and falling behind by 15. But the second half was a different game entirely — TCU clamped down defensively and chipped away, eventually completing the comeback for the two-point win. The under was never in doubt, with the 130 combined points finishing well below the 145.5 line. Ohio State was favored by 2.5, making this an outright upset for the 9-seed.
Nebraska 76, Troy 47 — Nebraska dominated from start to finish, covering the 13.5-point spread with ease in a 29-point blowout. Troy never threatened — the Cornhuskers' win probability never dipped below 85%. The under crushed at 123 combined points against a 139.5 line, as Nebraska's defense smothered Troy's offense all game.
Louisville 83, South Florida 79 — Louisville covered the 3.5-point spread and the over barely squeaked through at 162 against a 160.5 line. The Cardinals led throughout but South Florida kept it close enough to sweat, never letting Louisville fully pull away until the final two minutes. A workmanlike win for the 6-seed.
High Point 83, Wisconsin 82 — The day's marquee upset. High Point, a 10.5-point underdog, trailed for most of the game and Wisconsin's win probability sat comfortably above 90% for long stretches. But the Panthers kept answering — Rob Martin was sensational, drilling three-pointers every time Wisconsin tried to pull away. The Badgers led 82-78 with under two minutes left, but High Point scored five straight to take a stunning 83-82 lead. Wisconsin had one final chance but Owen Aquino came up with a crucial block on Nick Boyd's driving layup attempt, and the Panthers held on — not just covering the 10.5-point spread, but winning outright. The over cashed easily at 165 against a 161.5 line, fueled by a frantic final five minutes where neither team could miss.
Duke 71, Siena 65 — The 1-seed survived, but this was anything but comfortable. Siena matched Duke shot for shot, trailing just 24-16 at one point before tightening the gap. Francis Folefac and Gavin Doty combined for six three-pointers to keep the Saints within striking distance all game, and Duke's win probability dipped to 63% in the second half. The Blue Devils never came remotely close to covering the 28.5-point spread — the cover probability flatlined near 0% from early in the first half onward. The under barely squeaked in at 136, just 1.5 points below the 137.5 line. A tight game that played much closer to a pick'em than a 1-vs-16 matchup.
Vanderbilt 78, McNeese 68 — Vanderbilt won by 10 but fell short of the 12.5-point spread. The Commodores controlled the game throughout — McNeese's win probability briefly touched 52% early but Vanderbilt quickly reasserted control. The under hit at 146 against a 148.5 line in a game that played out mostly to script.
Arkansas 97, Hawai'i 78 — Arkansas rolled as expected, covering the 14.5-point spread behind a 19-point victory. The over hit comfortably at 175 against a 158.5 line, with both teams pushing the pace. The Razorbacks were never in danger, holding a double-digit lead for most of the game.
Michigan State 92, North Dakota State 67 — The Spartans covered the 16.5-point spread with a dominant 25-point win. The over cleared 144.5 at 159 total points. Michigan State's defense forced turnovers early to build a comfortable lead, and the bench extended the margin in the second half. A stress-free opener for the 3-seed.
VCU 82, North Carolina 78 (OT) — North Carolina looked in complete control, leading 70-61 with five minutes left and the cover probability sitting at 77%. Then Terrence Hill Jr. happened. The VCU guard sparked a 14-5 run, capped by a driving layup with seconds remaining to force overtime at 75-75. In the extra period, Hill Jr. hit a dagger three-pointer to push VCU ahead 80-78, and UNC never recovered. The Tar Heels' win probability went from 96% to zero in about eight minutes of game time. The over cleared 150.5 comfortably at 160 total points, boosted by the overtime scoring.
Michigan 101, Howard 80 — Michigan cruised to a 21-point win, but the 30.5-point spread was always a bridge too far. Howard actually played respectably — the Bison matched Michigan's scoring rate for stretches and the 181 combined points sailed well over the 151.5 total. The Wolverines were never threatened (WP stayed above 97% all game), but the cover was dead on arrival against that massive number.
Texas A&M 63, Saint Mary's 50 — The 10-seed Aggies pulled the mild upset, defeating 7-seed Saint Mary's by 13 in a defensive slugfest. Saint Mary's was favored by 2.5 but never led by more than a few points. The 113 combined points came in well under the 149.5 total — one of the lowest-scoring games of the day. Texas A&M's defense made the difference in a game that was tight until the Aggies pulled away late.
Texas 79, BYU 71 — Texas led for most of this game despite being a 2.5-point underdog. BYU managed to stay within range but never established control — the Cougars' win probability barely cracked 64% at its peak, and Texas answered every mini-run. AJ Dybantsa kept BYU's hopes alive with clutch three-pointers down the stretch, but the Longhorns' balanced attack was too much. BYU's cover probability was essentially dead by halftime, dropping below 20% and never recovering. The under hit at 150 against a 156.5 line.
Illinois 105, Pennsylvania 70 — Illinois put up a dominant performance, covering the 25.5-point spread with a 35-point blowout. The over hit easily at 175 against a 150.5 line, as the Illini poured it on offensively. Penn briefly made it interesting early — Illinois' cover probability dipped to 7% in the first few minutes — but the 3-seed quickly asserted itself and never looked back.
Saint Louis 102, Georgia 77 — The most lopsided result of the day. Saint Louis, a 9-seed, dismantled 8-seed Georgia from the opening tip, racing out to a 30-18 lead midway through the first half and never looking back. Georgia was a 1.5-point favorite but spent the entire game in a hole — the Bulldogs' win probability dropped below 50% within the first five minutes and kept sinking. The 179 combined points obliterated the 167.5 total, with Saint Louis cracking the century mark in a dominant performance. It was over before halftime.
Houston 78, Idaho 47 — Houston took care of business against the 15-seed, covering the 24.5-point spread with a 31-point victory. The under hit at 125 against a 137.5 line, as Houston's defense held Idaho to just 47 points. A dominant, low-drama opener for the 2-seed.
Gonzaga 73, Kennesaw 64 — Gonzaga won comfortably but never came close to covering the 20.5-point spread, winning by just 9. The Bulldogs' win probability never dipped below 80%, so there was no drama on the moneyline side, but the cover was dead from the start — the cover probability peaked at 50.1% and spent most of the game near zero. The under hit easily at 137 against a 152.5 line, as Gonzaga's defense kept the pace slow. A routine win for the 4-seed, but a loss for anyone who laid the big number.