Maybe it was the red jerseys.

For the announced 17,950 fans at Xfinity Center on Saturday, the red uniforms with ‘Wisconsin’ stitched across the front in white lettering held a simple meaning: the enemy.

But for Terrapins men’s basketball center Diamond Stone, the jerseys hold a greater meaning. They are the uniform of his home-state school, the one where he’s Public Enemy No. 1.

To them, Stone is many things: a brat; a traitor; an ingrate. When the Terps traveled to Madison, Wisconsin on Jan. 9., fans hurled insults at Stone from beginning to end. They booed every time he touched the ball. They teased him, alluding to rumors of the teenager’s low ACT scores.

So maybe, just maybe, when Stone found himself on top of Wisconsin forward Vitto Brown with less than two seconds left in the Terps’ 70-57 loss — their first home defeat in more than a year — some of those insults popped into his head.

Maybe it was Brown’s red jersey.

Picking himself off the floor, Stone placed his left hand on Brown’s head and crushed it into the hardwood. Brown’s skull ricocheted. Watch the video if you’d like, but it’s scary.

Stone stayed in the game, and ended up scoring six of his 10 points in the second half.

It wasn’t enough.

With a few ticks more than two minutes remaining, fans started filing for the exits. It was a surreal moment, as Xfinity had been home to good vibes for so long. For more than 14 months, in fact.

But on a night with several notable figures in the crowd — Torrey Smith, Dez Wells, DJ Durkin, Chris Wilcox, among others — Saturday took an unfamiliar turn into the realm of heartbreak.

My postgame grades offer a glimpse of what went wrong:

Guard Melo Trimble: C-

First, the positives: Trimble went 8-for-10 from the line, scored 10 points and had six assists. The bad? The face of the team shot 1-for-14 from the floor; he also had five turnovers. Of course, the Terps lost.

Guard Rasheed Sulaimon: B+

Sulaimon was hot early on, scoring six points in the first seven minutes. He wasn’t as effective in the second half, shooting 1-for-4 from behind the arc, but he still finished with a team-high 17 points.

Forward Jake Layman: B-

With forward Robert Carter Jr. fighting foul trouble in the first half, Layman slid onto forward Nigel Hayes, who played better than when Carter was guarding him earlier. Layman did add 10 points and five rebounds, though.

Forward Robert Carter Jr.: C+

Carter plays with fire, which is usually a great thing. Not tonight. He picked up four personal fouls, limiting his playing time to 22 minutes, the lowest of the starters. As a result, he attempted just five shots, and wasn’t able to help the Terps when they dearly needed some. He finished with six points and eight rebounds.

Center Diamond Stone: C-

I usually only base these grades on play. But what Stone did to Brown was unacceptable and unnecessary. You don’t mess with people’s heads. His 10 points on 5-for-6 shooting and four blocks would’ve warranted a B-, but I’m docking a full letter grade for the incident.

Guard Jaylen Brantley: B-

With guard Jared Nickens (zero points in 12 minutes) again being a non-factor on offense, Brantley played 10 quality minutes, scoring four points, hauling in three rebounds and forcing one steal.