NBA in-season tournament quarterfinal takeaways: Tyrese Haliburton ready for spotlight; Zion Williamson still not an alpha dog

Well, that was fun. The crowds on the opening night of the NBA's in-season tournament single-elimination quarterfinals created a playoff atmosphere. The play was not as crisp as it should be come April, but there was an intensity on the court that we have never before seen in December, and for that the league wins.

On last season's first Monday of the month, NBA TV hosted the only nationally televised game of the night, featuring a Phoenix Suns team playing without four rotational players in their third game in four nights, and the Dallas Mavericks hammered them, leading by as many as 27 points in the second half of a 130-111 win.

Not this time. The league cleared its schedule on Sunday, ensuring everyone was rested for its first-ever night of knockout games. The evening's first game featured 15 ties and 16 lead changes, ending in a 122-112 upset win for the up-and-coming Indiana Pacers opposite the championship favorite Boston Celtics.

In the nightcap, the lead swung wildly in both directions of a battle between Western Conference playoff hopefuls, and the New Orleans Pelicans beat the Sacramento Kings in an entertaining affair 127-117.

The Pacers and Pelicans respectively await the winners of Tuesday's quarterfinal games in the East (New York Knicks at Milwaukee Bucks, 7:30 p.m. ET, TNT) and West (Suns at Los Angeles Lakers, 10 p.m. ET, TNT).

We learned a lot more than we figured we might when the NBA first announced this thing, and it was just one night of single-elimination action. This should escalate once the tournament moves to Las Vegas for Thursday's semifinals and Saturday's title game. Hand it to commissioner Adam Silver. This was his baby.

Indiana Pacers 122, Boston Celtics 112

We learned that Indiana's Tyrese Haliburton is built for this spotlight. He logged his first career triple-double, totaling 26 points (10-18 FG, 5-11 3P, 1-1 FT), 13 assists (zero turnovers) and 10 rebounds in a season-high 40 minutes. It was not just the totals, either. He worked all-world defender Jrue Holiday for a 3-pointer that gave the Pacers a 101-99 lead with fewer than four minutes remaining in the fourth quarter. He drilled another from 27 feet to break a 105-105 tie with 1:33 left, drawing a foul from Jaylen Brown and drilling a free throw for a 109-105 advantage his team would not relinquish. That was grown-man stuff from a 23-year-old with no playoff experience against a team full of veterans who have all made a ton of deep postseason runs.

Heck, we learned the Pacers might be a real playoff threat. They took 32 points from Jayson Tatum, 30 from Brown, and hit back. Aaron Nesmith scored 11 of his 14 points in the fourth quarter and hounded Tatum like he traded Boston's former lottery pick to Indiana. Buddy Hield and Bennedict Mathurin, who have swapped spots in the starting lineup, combined for 37 points on 8-for-13 shooting from deep, teaming up to provide a consistent scoring punch from the wing for Haliburton. Hield is in his eight season and has never appeared in a playoff game. Mathurin was a rookie on the Indiana team that won 35 games last season.

We learned the Pacers can dial up their defense. They entered Monday's game with the league's second-worst defensive rating (120.8 points per 100 possessions), and while the end result was not much better against the Celtics, they made things difficult for Boston when they needed to. Indiana held the Celtics to 40% shooting in the first and third quarters and forced turnovers on three of their final seven possessions. And Tatum's persistent targeting of Haliburton gives the Pacers an indication of what must be improved.

We learned Indiana might need more size. Backup Jalen Smith missed Monday's game with a bone bruise on his left knee, leaving Myles Turner as the lone true big, and the Celtics outrebounded the Pacers by 15. They were fortunate to make seven more 3s and nine more free throws to offset their deficit on the glass.

We learned Boston may not have solved its biggest weaknesses in the offseason. The ball still was not moving enough when the game got tighter, and when it did, the Celtics were sloppy with it. They committed 18 turnovers to Indiana's six, another loss on the margins reminiscent of last season's postseason woes.

We learned Boston's Joe Mazzulla could not dispel fears over his in-game coaching. Going nine deep into his rotation gives him the excuse he did not treat this like a true playoff game, but his rotations left a lot of offensively challenged lineups on the floor. Indiana also repeatedly found holes in his defense, and the Celtics bench called another timeout too late on Indiana's 18-5 run midway through the third quarter.

We learned the Celtics could use one more reliable reserve. Sam Hauser connected on five of his seven 3-point attempts, but third guard Payton Pritchard finished scoreless. Dalano Banton got the call over fellow minimum-paid wings Oshae Brissett, Svi Mykhailiuk and Lamar Stevens and also gave them nothing.

We learned concerns about Boston's frontcourt health are real. Kristaps Porziņģis missed a fourth straight game with a calf strain, and his absence was felt several-fold. Al Horford, the 37-year-old veteran center, exceeded 30 minutes for the fifth time in six games after averaging 24 minutes in his first 12 appearances. Luke Kornet picked up the rest of the slack, and while he performed admirably, the gap between him and Porziņģis is the difference between a title favorite and a roster akin to the one that fell short last season.

New Orleans Pelicans 127, Sacramento Kings 117

We learned Pelicans forward Zion Williamson is still not a killer. He scored 10 points on eight shots and deferred to Brandon Ingram and CJ McCollum, since they have far more versatile offensive games, but isn't the best version of their team one with Williamson as its alpha dog? That is what we thought on the most dominant stretches of his career, but he was on the bench for his team's fourth-quarter push on Monday.

We learned Ingram might have a higher playoff ceiling than we imagined. He averaged 27 points on 48/41/83 shooting splits in his lone playoff appearance, a first-round loss to the Suns in 2022, and he delivered a 30-8-6 on 10-of-20 shooting against the Kings. None of it matters if they cannot figure out how best to maximize he and Williamson, who was injured on that playoff run and less than stellar on Monday.

We learned Pelicans head coach Willie Green is more comfortable leaning into offense, relying heavily on McCollum three games into his return from a second collapsed lung. In his 12-game absence, the lengthy combination of Herb Jones and Dyson Daniels unlocked a defense that performed at a top-five level when both were on the floor. McCollum delivered offensively, scoring 17 points on 14 shots, but New Orleans was outscored by four points in his 36 minutes. Daniels played six minutes, and the Pelicans were +8 in them.

We learned (or we were reminded) that New Orleans' Trey Murphy III and Sacramento's Keegan Murray are two of the game's best young role players. Both recently returned from injury, and both found their spots on Monday. Murphy scored 16 points in 30 minutes off the bench and finished a game-best +24. Murray countered with 15, despite reaggravating the back injury that cost him four games at the end of November.

We learned Sacramento's defense is still not ready to contend. The Kings got 30 points from De'Aaron Fox, a triple-double from Domantas Sabonis (26-13-10) and 21 points off the bench from Malik Monk, but they had no answers for New Orleans' offense. They have no defensive anchor and few more plus defenders.

We learned Trey Lyles does not like Jonas Valančiūnas, since the Kings forward threw a punch at the Pelicans center after they tussled for a rebound. If you needed evidence that the in-season tournament means more than your normal regular-season game, look no further than a dude throwing down on someone a few inches taller and a few dozen pounds heavier. That and Nesmith giving Boston's Derrick White the "too little" taunt in the fourth quarter of the night's opener. Let the fun resume on Tuesday night.