LAS VEGAS -- Seconds before Thursday afternoon's opening tip, the T-Mobile Arena public address announcer attempted to hype up the crowd.

"We can't hear you!" he hollered as the Indiana Pacers and Milwaukee Bucks lined up for the beginning of the first semifinal of the NBA's in-season tournament, the league's grand experiment to inject excitement during the part of the sports calendar dominated by football.

There wasn't too much to hear at the moment, not with the thousands of empty seats for the 2:13 p.m. local tip-off. The bright theater lighting on the court, which was painted an eye-popping blue with a red stripe down the middle, took attention away from the awkwardness of such a sparse crowd for a mid-afternoon tip between two small-market Midwest teams based 1,800 miles or so away.

The atmosphere felt like a No. 4 vs. No. 13 March Madness matchup between two faraway schools. Fortunately, that changed as the crowd filled the vast majority of the seats. The announced attendance for the Pacers' 128-119 win was 16,837 fans -- the night's second game between the Los Angeles Lakers and the New Orleans Pelicans was a sellout at 18,017 -- and there were a lot of happy fans.

"This is dope," DeJuan Smith told ESPN at halftime. A Milwaukee native who moved to Vegas 17 years ago, Smith was ecstatic to take his sister, Kelis Henderson, to her first NBA game and to watch their favorite team together. They both wore Giannis Antetokounmpo jerseys.

"It might have been better to have it a little bit later, but it's a good vibe," Smith added.

NBA fans embraced the scenes during the in-season tournament semifinal games in Las Vegas. Jeff Bottari/NBAE via Getty Images

Smith and Henderson considered attending both semifinals -- tickets were sold separately with the arena cleared out between games -- but tickets to the Western Conference game were selling for twice as much as the East matchup on the secondary market.

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That's because the second semifinal felt like a relocated Lakers home game. That was widely anticipated, as Vegas is essentially Lakers territory, as evidenced by the large crowds their games usually draw at the Las Vegas Summer League. The Pelicans were booed during starting lineup introductions, and the packed crowd roared after every Lakers bucket during the team's 133-89 win.

There was even a scattered "MVP!" chant for LeBron James when he went to the free throw line early in the first quarter. James' pull-up 3 from a step past the trophy logo at midcourt early in the second quarter sent the crowd into a frenzy.

"It's funny, my trainer was like, 'You know, one thing you haven't done in your 21-year career is be in the Final Four,' before the game started today," James said about the game's tournament atmosphere. "I chuckled a little bit.

"I went to the [high school] state championship every year, all my four years. ... This is definitely heightened, being NBA players and what's at stake."

It's less than a four-hour drive from Los Angeles, but Vegas residents made up the majority of the crowd. That was apparent during both national anthems. Loud shouts of "KNIGHTS!" drowned out the word "night" in the song's lyrics, a tribute to the NHL's Vegas Golden Knights, one of the arena's primary tenants along with the WNBA champion Las Vegas Aces, who had several players attend the Pelicans-Lakers game.

The NBA invited several of its past stars as VIP guests, a list headlined by Hall of Famer Julius Erving.

Brian McDowell, a Denver resident who grew up in Indianapolis, booked travel and bought tickets for himself and his 14-year-old son, Ty, as soon as the Pacers closed out their quarterfinals upset victory over the Boston Celtics. McDowell raised his son as an Indiana sports fan, and they pounced on the opportunity to see the Vegas sights and watch their favorite NBA team make some history.

"This is my first time having some competitiveness in my sports fandom," Ty McDowell told ESPN. He wore a yellow Myles Turner jersey, while his dad wore a blue Tyrese Haliburton jersey.

But there might have been as many Lakers jerseys in the stands as Pacers and Bucks combined. There were also a wide variety of other teams represented, including a lot of throwbacks to retired legends, a list dominated by Kobe Bryant and Shaquille O'Neal.

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"NBA fans, man," Turner, who scored 26 points for the Pacers, told ESPN with a big smile. "I think it's been great for the league, because the whole point of this was [the] NFL gets all the viewership right now.

"We have this buzz, this excitement."

The Pacers, in particular, are basking in the spotlight that has come with their run to the first in-season tournament final. Indiana is a small-market franchise that is on the rise after years off casual NBA fans' radars. The Pacers were scheduled to have only one nationally televised game this season, but they earned the privilege of that audience by advancing to all three elimination games of the tournament, a chance to show the basketball world the Haliburton-led offense that is lighting up the league with unprecedented efficiency.

"Honestly, it was amazing, bro, because in a small-market city we don't get as much exposure," Turner told ESPN. "So to have a chance to come out here and have that excitement for our team, actually hear people cheering for our team and whatnot, I mean, it was a different type of vibe than just being at the crib.

"There's some teams like the Lakers and Boston that have traveling fans, but we don't get that as much. Getting all the love out here like that at a neutral site was amazing."

It's likely that Las Vegas will have its own NBA franchise soon, as the league is expected to welcome two expansion teams after the next national TV deals are finalized. Pacers coach Rick Carlisle called it "the worst-kept secret in the world" that Vegas will get one of those teams, and he considers Thursday's atmosphere as further evidence that the market is ready for the opportunity to support an NBA franchise.

"I think the turnout today shows that there's certainly interest in the NBA game," Carlisle said. "I've been around this a long time. I believe that the NBA can make just about anything happen. The in-season tournament [has had skeptics] for many years, and right now, it's all the buzz."