Maryland forward Jalen Smith battles Belmont center Seth Adelsperger for a loose ball during the Terps' first-round win. (Jonathan Newton/The Washington Post)

JACKSONVILLE, Fla. — When notifications flooded Jalen Smith’s phone Thursday night, the freshman’s main concern was what his father had to say. Smith had just led his team in scoring, propelling Maryland toward its much-needed postseason win over Belmont, yet Smith’s dad pointed out one of his son’s missed free throws.

Maybe that’s the moment you remember if you’re a father, whom Smith calls his biggest critic. But it’s not the one you harp on if you’re a Maryland fan — or even a casual viewer — who watched what was perhaps the most exciting game on the first full day of the NCAA tournament.

Smith’s March Madness moment came with his team clinging to a one-point lead with less than two minutes remaining. Off a pass from Darryl Morsell, Smith threw down a dunk, drew a foul and completed a three-point play.

That’s the video clip that accompanied Smith’s name Thursday night on social media, the one that defined the freshman’s afternoon. Smith scored 19 points and pulled down 12 rebounds. He played aggressive, and he was what Maryland needed. For someone who says, “Confidence is a huge part of my game,” Smith’s performance was also one that could fuel Maryland heading into Saturday’s second-round game against LSU.

In Naz Reid and Kavell Bigby-Williams, the Tigers have a formidable frontcourt presence to match the Terrapins’ duo of Smith and sophomore Bruno Fernando. The pair that best survives that matchup will probably determine the winner as the teams vie for a spot in the Sweet 16 game that’ll be played at Capital One Arena in Washington.

“What [the game is] going to come down to, I think it’s very simple: It’s going to be who wins the paint and who wins the rebounding battle,” LSU interim head coach Tony Benford said. “It’s going to be that simple.”

Fernando has been a constant force for the Terps. In the massive leap he took heading into his sophomore campaign, Fernando learned how to better handle when opponents try to contain him with double-teams, and he has improved as a passer. Fernando’s 14 points and 13 rebounds against Belmont marked his 21st double-double.

“You look at Bruno,” Benford said. “He scares you once you look at him.”

And then there’s Smith, who’s had an inconsistent year as he has waded through the expectations that come with being a five-star recruit and a McDonald’s all-American. Throughout the season, Maryland Coach Mark Turgeon has said his team needs Smith to play well.

Fernando’s dominance is crucial to Maryland’s success, but when Smith plays like he did Thursday, the challenge for opponents becomes even more daunting. With a size advantage on his side against Belmont, Smith grabbed eight offensive rebounds and shot 8 for 9 from the field. All of his shots came in the paint, even though in the previous five games he attempted 15 three-pointers and made five.

“He’s been up and down, but I think recently he’s been up more than down,” freshman forward Ricky Lindo Jr. said. “That’s good for us, especially this time of year. It’s really important that he’s up. When he’s up, we’re all up.”

That theory checks out: Maryland is 11-0 when Smith scores at least 15 points.

Smith averages 11.6 points, but he’s struggled at times. After Maryland’s win over Indiana, just three days after Smith’s season-high 21 points against Minnesota, Turgeon said he felt bad for the freshman, who struggled throughout a two-point showing. Later in January, Turgeon called a road loss to Michigan State an eye-opener for Smith, who couldn’t find any rhythm against the physical Spartans.

“I know a lot of people expected him to almost carry us and be that guy for us,” said freshman Aaron Wiggins, who lives with Smith in College Park. “For him to have a couple bad games, it was really tough for him. But at the same time, he knew we all had his back. We were going to encourage him regardless of what happened on the court. We always had him.”

Most of Smith’s disappointing moments have been followed by ones that prove his ability, and he has been trending upward. He is averaging 13.2 points and 7.8 rebounds over his past five games. That confidence helps, especially because he’s so young, said Morsell, a sophomore guard who was Smith’s teammate at Mount Saint Joseph High in Baltimore.

“I always tell him just don't take a back seat to anybody,” Morsell said. “I like Jalen when he's aggressive, when he's looking to score, when he's attacking the rim.”

That’s the version of Smith that shined against Belmont. Fernando, who rooms with Lindo on road trips, said the two talked before the game about how they expected Smith to have a great game. He had been practicing well and seemed prime for a day like Thursday. Freshman Eric Ayala could tell Smith was ready based on a conversation that oozed confidence before the matchup.

“I know what Stix is capable of,” Ayala said, referring to Smith by the nickname given to him when he was a tall and lanky kid. “Whenever he’s not doing that or not playing to that capability, I get on him because I know he can bring that to the table. And he can do that whenever he wants.”

So when Morsell secured the loose ball after a scrum late in the second half Thursday, he knew where Smith wanted it and went with the safe pass rather than a difficult lob.

From there, Smith “absolutely pummeled it,” beloved senior benchwarmer Andrew Terrell said, describing the dunk. Then social media helped preserve the moment for Smith, who turned 19 last week. As the tournament continues, the stage will only grow for Smith.

“Jalen’s still a kid,” Morsell said. “But he knows he has talent."

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