MILWAUKEE – For four years, John Henson has looked across the locker room at Giannis Antetokounmpo. He remembers the skinny, 6-foot-9, 196-pound teenager who began his NBA career with little fanfare. And he marvels at the rock-solid, 6-11, 222-pound superstar Antetokounmpo has become.

“When you saw his older brother [Thanasis], you knew he was going to be big,” Henson said, laughing. “But, man, I didn’t know he was going to be this big.”

The biggest story in the first week of the NBA season is the player who is still growing. At 22, Antetokounmpo is coming off a 22.9-point-per-game season that culminated with some hardware — the NBA’s Most Improved Player Award. Through four games this season, Antetokounmpo is averaging 36.8 points on 65.9 percent shooting — and has found himself in the conversation for MVP.

Ask Bucks officials to pinpoint the reasons for Antetokounmpo’s rise, and the answers are similar. They begin with his work ethic. “It’s right up there with LeBron’s, with Kobe’s,” Bucks coach Jason Kidd told The Vertical. “He lives in the gym.” Almost literally. When the Bucks moved into a new $31 million practice facility this summer, Antetokounmpo asked Jon Horst — “Mr. Jon”, as Antetokounmpo refers to Milwaukee’s 34-year-old GM — if he could buy the old one. He wanted to convert it into a house. Horst told Antetokounmpo that for the cost of the facility, he could buy a new house and build a gym in it. Antetokounmpo agreed.

Said Horst, laughing, “He’s passionate about gyms.”

Sean Sweeney knows. Since coming to Milwaukee with Kidd in 2014, the assistant coach has been Antetokounmpo’s shadow. “He goes everywhere with me,” Antetokounmpo told The Vertical. “Spain. Greece. Fresno. All over the place.” When Antetokounmpo gets up in the morning, often there is a text from Sweeney telling him he’s at the gym. “Some days, I tell him, ‘I’m tired of seeing your face,’ ” Antetokounmpo said, smiling. “Some days, he says it to me.”

An Antetokounmpo workout can happen anytime. In 2015, Antetokounmpo was unhappy with the way he defended in a road game. When the Bucks’ plane touched down back in Milwaukee, he asked Sweeney to come to the practice facility to run through a few drills. “The gym is his sanctuary,” Kidd said. “It’s his home.”

The Bucks have mined Antetokounmpo’s talents masterfully. It began in 2013, when then-coach Larry Drew played Antetokounmpo 25 minutes per game, a trial by fire that team officials say accelerated his development. Kidd has guided him to the next level. He has shown tough love (benching him in 2015) and empowered him (making him a part-time point guard last season), pushing him to become an unstoppable, two-way player.

“He can be Magic Johnson and KG [Kevin Garnett],” Kidd told The Vertical. “When he puts his mind to it, he can do everything defensively.”

Kidd recruited Garnett, his former player, last season to swing through Milwaukee on his post-retirement tour. He put Garnett with Antetokounmpo and Thon Maker, the Bucks’ stringy, 7-1 then-rookie center, in the hopes that KG could “breathe that spirit into them.”

“I wish I had a GoPro [camera] for that,” Kidd said. “They were just locked in to everything KG was saying.”

Antetokounmpo remembers Garnett’s words well. “Have a killer mentality,” Antetokounmpo told The Vertical. “Go out there and play to kill. For me, I’m not going to say I was born with it, but it’s coming. I want to win. It’s hard, you know? With back-to-backs, a lot of games, sometimes you think, ‘I’ve got to take a day off today.’ But you have to push through it. The greats did. KG said you have to have that mentality. If you are hurt, you have to fight through it.”

Veteran guard Jason Terry played two seasons with Garnett. He sees similarities with Antetokounmpo. “Not so much the physical, the mental,” Terry said. He recalled a play against Boston, in Milwaukee’s season opener, when Antetokounmpo barreled down the lane, finished at the rim and drew a foul. “He thumped his chest and said, ‘That’s what I do,’ ” Terry said. “It’s a kill mentality. Our team vs. them. He’s oozing confidence right now. Not overconfidence — just a confidence knowing [he] put the work in, believes in his skills and trusts his training.”

Indeed. Antetokounmpo has been a monster, on both ends of the floor. Against Portland on Saturday, Antetokounmpo scored a career-high 44-points. But it was back-to-back defensive plays — a poke-away steal of 6-4 guard C.J. McCollum and a block of 6-11 center Jusuf Nurkic — that sealed a Milwaukee win. Against Charlotte on Monday night, Antetokounmpo stuffed the stat sheet with 32 points, 14 rebounds and six assists — and a block of Jeremy Lamb with the Bucks up five with 30 seconds left to clinch the win.

“He’s gotten everybody’s attention,” Blazers coach Terry Stotts said. “He just keeps getting better. He’s figured out what works for him. Everyone goes into the game with the same scouting report on great players, whether it is [Russell] Westbrook, [Stephen] Curry or [Kevin] Durant or Giannis. You try to limit them as much as possible. But they are great for a reason.”

Great — and getting better. As good as Antetokounmpo is, he is years from reaching his full potential. He’s electrifying in the open floor and impossible to defend off the dribble. He has a rapidly developing step-through move — think Manu Ginobili’s, but longer — and great touch around the rim. But he is a non-factor from three-point range and his low-post game is still developing. On Monday, Antetokounmpo found himself switched on to Dwight Howard. Instead of facing Howard up, Antetokounmpo dropped his shoulder and tried to overpower him.

Said Kidd, “He was trying to show his strength.”

Kidd smiled as he spoke. The occasional slip-up is a small price to pay. He sees the confidence growing in Antetokounmpo, the floor opening up in front of him. The potential is limitless.

“I kind of know when I can score the ball now,” Antetokounmpo said. “In previous years, I was taking the ball and just racing guys. Now I kind of know my spots, where are my sweet spots. If I’m in the middle of the court, I’ll be able to make plays. I know that guys can’t guard me one-on-one. … I just know when I’m able to score, when I’m able to make a play. My first few years it was always a turnover. I was always getting offensive fouls because I was running fast, speeding up myself. It’s slowed down a little bit for me.”

Slowed down — now that’s a scary thought. “I don’t think he knows how good he can be,” Terry said. Indeed, there remains an innocence to Antetokounmpo. Late Monday night, Antetokounmpo turned to Tony Snell, the backup swingman whose locker was next to him. I owe you $70, Antetokounmpo told Snell. Don’t let me forget. Snell smiled and said he wasn’t worried about it. No, no, no, Antetokounmpo said. I owe you $70. The back and forth continued until Snell agreed to take the $70 out of Antetokounmpo’s per diem on the next trip. He bumped fists with Antetokounmpo, laughed and walked away.

That’s Antetokounmpo. Lighthearted off the floor. Cold-blooded on it.

THREE POINTS

Lonzo takes L.A.

Lonzo Ball is going to be a good player. How good remains to be seen, but three games into his career, playing the NBA’s most challenging position, Ball has shown enough to make believers out of many who have watched him. Lakers coach Luke Walton likened Ball’s singular focus during games to Kobe Bryant’s. Pelicans coach Alvin Gentry told reporters that he didn’t see how Ball could possibly fail.

Ball is good, and his ability to wall himself off from the noise around him is remarkable. After stifling Ball in the season opener, Clippers guard Patrick Beverley became the latest to confirm that Ball had a bull’s-eye on his back. “I told [Ball] after the game, due to all the riff-raff his dad brings, that he’s gonna get a lot of people coming at him,” Beverley said. “He has to be ready for that.”

Ball can’t change history, but he can do something about his father’s outlandish comments moving forward. There’s nothing sinister about LaVar Ball. His interview, if you want to call it that, with ESPN after Lonzo’s debut was cartoonish, an appearance more for his brand than a defense of his son. Likewise, LaVar Ball had a sneaky smile when he declared that the Wizards — in town for a matchup with the Lakers on Wednesday — “better beware, because Lonzo isn’t losing again.”

Harmless — except when those comments are noticed by the Wizards, which they were, courtesy of a tweet storm by Marcin Gortat, who vowed that John Wall was going to “torture” Lonzo for 48 minutes. The Lakers don’t seem to be bothered by LaVar’s antics, and Lonzo is as reserved as LaVar is outspoken. But how many times can LaVar mouth off before Lonzo’s teammates tire of it? How many opponents will take exception to LaVar, and take it out on Lonzo on the floor? When the midseason grind hits, LaVar provides excellent motivation.

Maybe it’s all meaningless. The Lakers are bad — L.A. is 1-2, with only a win against the woeful Suns in the first week of the season — and Lonzo’s game could be sharpened for the future by getting an opponent’s best every night. But Lonzo is under enough pressure as the de facto new face of one of the NBA’s flagship franchises. Does he really need anymore?

Did Yi Jianlian really work out against a chair?

Loved this Deadspin piece, which took a deep dive into the legend of Yi Jianlian’s workouts against a chair. That Yi — a 2007 lottery pick who played five seasons in the NBA — held pre-draft workouts in which his opponent was literally a folding chair has become a part of his brief NBA history. As Deadspin noted, there is no video. To date, no one can recall specifically seeing Yi work out against a chair.

I can.

First, to be clear: Yi did not conduct a full workout against a chair, at least not the one I saw. In the spring of 2007, I was dispatched by Sports Illustrated to write something on Yi. It was a multipurpose assignment; whatever I would write for SI, I would flesh out and write a longer cover piece for the new SI China. So through Yi’s agent, Dan Fegan, I arranged to sit in on Yi’s workout with the Sacramento Kings.

The workout wasn’t all that memorable, but three things stuck out. First, there were a lot of drills that showcased Yi’s athleticism. At 7-feet, 246 pounds, Yi was an excellent athlete, and I recall seeing a lot of him getting out in transition. Second, he wasn’t working out against anybody. Not unusual — it makes little sense putting a raw, Chinese player in against a more polished college star.

And third: There was a chair. I don’t recall Yi posting up against it (that wouldn’t make much sense, anyway) or dribbling around it. But I remember when Yi was running through catch-and-shoot drills, the chair was used as a prop for a screener. He would run around the chair, catch and fire midrange jumpers.

So, yes, a Yi Jianlian chair workout story is real — though not as interesting as the legend of it became.

Toronto (sort of) gets the band back together

When the Raptors’ season ended with a four-game sweep by Cleveland in the conference semifinals, it was reasonable to wonder if there would be substantial changes in Toronto. The team had several key free agents — Kyle Lowry and Serge Ibaka the most notable — and a pricey payroll that had yet to yield postseason results.

Last week, I asked Raptors GM Masai Ujiri: Were you tempted to blow the whole thing up?

“I think some of the changes we made were radical,” Ujiri told The Vertical. “We lost Cory Joseph. Patrick Patterson. P.J. Tucker. Those guys were pretty good players. For us to make a change there, to put our young guys on the court, to give them this platform to perform, I think it’s somewhat of a radical change. Our core, our starting five, is basically the same. The rest of our guys are young guys. We have to know what we have. This is an opportunity for them. They were always kind of hidden. We had to figure out where these guys are. It doesn’t look that radical, but it’s a big change for us.”

So far … pretty good. Monday’s 101-97 loss in San Antonio was Toronto’s first of the season. The inexperienced bench has been a bright spot. Ball movement — a problem for Toronto in recent years — has been excellent, and newcomer C.J. Miles has added a 3-point shooting presence that was missing from the second unit last season. The Raptors’ bench is versatile, mobile and plays with energy.

Change has come internally, too. When last season ended, Ujiri and head coach Dwane Casey spent weeks discussing how to improve. Style of play became the focus. Ujiri believed the team needed to get away from the isolation-heavy offense. He thought some complacency had set in. The team needed, Ujiri said, a “culture reset.”

“You don’t want to get complacent,” Ujiri said. “It can’t be, ‘We’re a playoff team and then what?’ We looked at every department. On-the-court stuff, off-the-court stuff, how we scout. All that stuff we had to refresh a little bit. It was good for us. But the style of play was a focus, as was the strength and conditioning.”

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