SEATTLE — When there was no one left to celebrate with him, Derik Queen clapped by himself. He stared into the crowd. He bounced a little. The author of a forever moment, the man who finally changed Maryland’s last-shot fortunes, basked as he waited for a hero’s postgame interview.

Queen, a 6-foot-10, 246-pound freshman from Baltimore who plays with grace and guile, let his mouthguard dangle from his lower lip. It’s a familiar, Stephen Curry-like habit, but this time he was so full of joy that if he smiled any wider, that thing would have fallen to the hardwood. He wouldn’t have had to pick it up, either. In fact, he doesn’t have to worry about any menial chores for the rest of his life. Someone in red will gladly take care of them.

On Sunday night, with a Sweet 16 appearance on the line, Queen took an inbounds pass from Ja’Kobi Gillespie with 3.6 seconds remaining, whirled to his left and used his exquisite footwork to dance into a fadeaway jumper that smooched the glass and dropped into the basket as time expired.

He posed, arms down, fists clenched, as Rodney Rice jumped onto his back. Then the entire Maryland men’s basketball team arrived to celebrate an improbable 72-71 victory over Colorado State.

“That was my first game-winner,” Queen said later, grinning.

To which Coach Kevin Willard replied: “I wouldn’t have given it to him if I had known that.”

Actually, Queen refused to let the coach call the play for anyone else. It was time to redefine what had been a hard-luck season for the Terrapins. They had lost four one-possession games, including two on buzzer-beaters. One of them was a half-court heave by Michigan State guard Tre Holloman.

Queen had felt enough last-second pain. After Colorado State guard Jalen Lake made a three-pointer to give the Rams a 71-70 lead with 6.1 seconds left, Maryland rushed the ball to half court and called a timeout. Willard had a play in mind, but he looked at his players and asked a question.

“Who wants the ball?” he said.

“I want the [expletive] ball,” Queen said without hesitation.

“Once he said that, it was a pretty simple decision,” Willard said.

For the first time since 2016, Maryland has advanced to the Sweet 16. The Terps, the No. 4 seed in the West Region, will travel to San Francisco to play No. 1 Florida, the hottest team in the country, on Thursday. Since winning the national championship in 2002, this is just the third time Maryland has reached a region semifinal.

In perception, the difference between a second-round close call and a Sweet 16 appearance is enormous. Clearly, Colorado State performed better than a No. 12 seed in this tournament, but if Maryland had lost to the Rams, it would have felt like a major opportunity lost during a critical time for the program. It would have sharpened criticism of Willard, who made multiple public challenges over the past week for the university to strengthen its commitment to the program.

The Terps needed this miracle. Queen, a monster talent with a carefree attitude, was happy to provide it.

“I knew we were due for one,” said Queen, who finished with 17 points, six rebounds and two blocks. “And I had to — had to! — make this.”

He fell off-balance during the drive. It did not matter. He jumped off the wrong leg. It did not matter. Debate about whether he traveled on his way to the basket raged on social media immediately afterward.

Queen, unflappable and likely on his way to the NBA at tournament’s end, couldn’t be denied. After he was emphatic about wanting the ball, Willard looked at the rest of the team.

“I saw guys’ confidence perk up a little bit,” he said.

For all the balance Maryland has in its starting five, Queen is the Terps’ most talented player. He’s the most gifted hooper just about any time he takes the floor. In college basketball, super freshmen don’t lead their teams to special places as much as they once did. The game belongs to upperclassmen now, many of whom transfer late in their college careers. This Maryland team has an ideal mix of veterans around Queen. He doesn’t have to carry the Terps, but when they needed a game changer Sunday, he delivered.

Maryland had to chase Colorado State the entire night. The Rams led 37-30 at halftime. Nique Clifford, the Rams’ star, kept plowing into the paint, hanging in the air and making difficult buckets in traffic. He finished with 21 points, seven rebounds and six assists. As the first half ended, he lifted his hand and pointed to the Colorado State section of the crowd to get louder.

By then, it was obvious the Rams hadn’t come merely to participate. They weren’t satisfied with a first-round victory over fifth-seeded Memphis. They played with the verve of a team certain it was just as good as Maryland.

Colorado State forced the Terps to play from behind almost the entire first half. Midway through, the Rams had built a 12-point lead, driving to the basket without fearing Maryland’s frontcourt duo of Queen and Julian Reese. The Terps tried to rattle them with a token full-court press, considerable in-your-face half-court pressure and even some aggressive trapping. But true to the Rams’ style, they didn’t turn the ball over much, and at times they exploited Maryland. Clifford had 12 points and three assists at halftime. Colorado State had assists on seven of its first 11 baskets. It shot 50 percent in the first half.

Queen scored 10 of Maryland’s first 14 points, keeping the Terps within striking distance. Queen made two three-pointers, continuing a trend of improved long-range shooting. Entering a Big Ten tournament semifinal against Michigan, the big man was 2 for 24 from three-point range this season. Since then, he has hit 4 of 7 attempts, including two in the first three minutes Sunday.

Trailing 24-12, Maryland went on a 10-0 run to trim its deficit to two. But the Terps went back to their old, befuddled ways, showing impatience against a scrambling defense and failing to move the ball well enough to exploit their size advantage.

They had to grind all game. Come back, fall back. Come back, fall back. But in the end, they had the ball last.

“For the first time, we have time left,” Willard said. “It’s our time to make it happen.”

“This is a moment they’ll remember for the rest of their lives,” Willard said.

It’s hard for a potential one-and-done freshman to become a legend. But with one audacious drive, Queen made a lasting impression. That mouthguard belongs in the trophy case now.