At halftime, things looked bleak for Duke. The Blue Devils allowed 43 points and found themselves trailing by 11 and staring at the biggest upset in the history of the NCAA Tournament.
Social media was ablaze with panic from the Duke faithful and mockery from the many Duke haters.
Jon Scheyer, who is one of the front-runners for National Coach of the Year, had to make an adjustment. His defense without Patrick Ngongba anchoring the middle had been a complete sieve: Siena was getting to the rim at will and challenging Cameron Boozer, and knocking down open looks from three.
Duke's aggressive man-to-man defense had spearheaded one of the nation's most efficient defenses this season, but Scheyer recognized it wasn't working and made a big shift for the second half that ultimately won Duke the game.
Scheyer shifted to a zone, figuring that Siena, a team that shot just 30% from three during the regular season, wouldn't continue shooting above their heads for a full 40 minutes, particularly with Gerry McNamara's iron man approach of having all five of his starters go the distance.
It worked.
Duke held Siena to 8-of-34 from the field in the second half. The 23.5% from the floor was the worst shooting half of the season for the Saints, according to Jeff Borzello, and they managed only 22 points, helping Duke escape with a six-point win.
Jon Scheyer's flip to a zone defense won the game for Duke in the second half vs. Siena
Duke's offense was only marginally better in the second half than in the first. It scored seven more points, but still managed only a 5-of-26 mark from three for the game. Siena smothered the interior, holding soon-to-be National Player of the Year Cameron Boozer to just 4-of-11 from the field, though he still managed a game-high 22 points thanks to a 13-of-14 mark from the free throw line.
If Duke's defense hadn't been elite in the second half, there's a good chance we're talking about the historic nature of this upset and opining about a wasted year for the Blue Devils.
Instead, Duke survived, advanced, and can shift its focus quickly toward 9-seeded TCU on Saturday.