BOSTON — It was early in the NBA tenures for both Brad Stevens and Giannis Antetokounmpo when the Celtics’ coach first laid eyes on the Greek phenom. Scanning the court, Stevens took in all 6’11 of the skinny teenager and thought, “Holy s.” (In the retelling of this story, Stevens really stopped short with the letter S, being the considerate Hoosier that he is.)

“He does some things,” Stevens said. “That’s the best way to put it.”

Giannis does indeed do many things. He’s not really a point guard, per se, but he brings the ball up the floor on occasion and initiates the offense. More often than not, the Bucks run their system through him in the high post, making him more of a point forward. Even that relatively modern designation isn’t exactly right because our terminology has yet to catch up to Antetokounmpo’s game.

In the open court, Giannis is breathtaking. He barely needs but a dribble or two to transverse the length of the court and his liftoff area begins around the free throw line. “Him in transition,” Stevens said. “I don’t know if I’ve ever seen anyone like him.”

He is also good for a dozen holy shit (sorry, Brad) plays a night. Some of these wind up on the nightly reel of gifs and highlights. Many of them, however, are subtle, fleeting moments. A behind-the-back pass here, an altered shot there. You simply can’t take your eyes off him at any moment and expect to get the full show. Blink and you’ll wish you hadn’t.

Giannis’ rise has been both steady and spectacular. He was a curiosity as a rookie, a phenom as a sophomore, and an intriguing talent in his third campaign when the Bucks began tilting their offense more and more in his direction. The wins, however, remained stagnant. The Bucks were a playoff team in his second season and a disappointment in his third, not that either were directly attributable to him. For the first three years of his career Giannis was a big part of a large ensemble, but not quite the man yet.

That’s all changed. What has elevated Antetokounmpo from the ranks of the young phenoms into a full-blown All-Star has been the melding of his phenomenal talents with a keener understanding of the game. That he has not had to sacrifice any of his spectacular gifts to reach this point makes him one of the most exciting prospects to come into the league since … ever, really. There is no precedent for a hyper-athletic 7-footer who plays like a forward and commands the game like a guard.

In his fourth season Giannis has experienced the biggest jump of his career. Everything is up, from scoring and shooting to playmaking, steals, and assists. Most importantly, the Bucks are winning games and their trajectory is once again pointed in the right direction. As we head down the stretch of the regular season, they are the most dangerous low seed in the entire bracket and the one that makes potential opponents in the East wary.

All that, and Giannis is still just barely 22 years old.

“I know for you guys it’s different, but when you see him in the gym every day and you see the work he puts in, it’s not really a surprise,” Greg Monroe said. “He’s never tired. Ever.”

18-year vet Jason Terry compared his work ethic to that of Dirk Nowitzki and marveled, “He has so much more basketball to go.”

His coach Jason Kidd attributed Giannis’ growth to his ability to listen, which sounded like a perfunctory compliment at first but made sense in the reasoning.

“He wants to be great,” Kidd said. “He thrives in the challenge of us putting more responsibilities on him, but I would say his ability to listen and digest what we’re saying (and then) to translate it onto the floor. To be given the ball at 21 years old at 7-feet tall, to run the offense and understand what we’re trying to do. There’s going to be some good and there’s going to be moments to learn from. He digests not just the good, but the bad too.”

Giannis himself echoed that refrain when asked the same question, reinforcing the messaging that his coach is providing.

“Listening,” he said. “That’s the most important thing. Usually when you’re this young you think you know everything but really you don’t know nothing. You got to keep listening.”

Even as he grows into his featured role, Antetokounmpo remains an unabashed delight. He is young and fun, commanding the post-game DJ role with glee. His English is fantastic and his manner is playful. He has not yet been beaten down into giving cliched, canned answers, bless his heart.

Responding to an on-court altercation with Celtic provocateur Marcus Smart that led to a flagrant foul on Smart, Giannis noted: “I thought he just flopped a lot. I wasn’t even mad about him tripping me. I touched him but I thought he oversold it. He’s a smart player. That’s why his name is Smart.”

On 24-year-old teammate Malcolm Brogdon, who it must be noted is two years older than Antetokounmpo: “He’s not a rookie in my eyes.”

Told that Stevens had made a similar comment, Giannis didn’t miss a beat: “Great minds think alike.”

Giannis can be charming and goofy and the stories of his early indoctrination into American culture were both hilarious and endearing. But as he told SI’s Lee Jenkins earlier in the season, “I’m not really that kid anymore.” Where once he was a League Pass fever dream, now he’s a legitimate franchise player.

That’s the biggest development of this Milwaukee season. With Giannis leading the way, the Bucks have suddenly become a very good basketball team even without injured scorer Jabari Parker. They have the best record in the East since the All-Star break and were tied with Portland for the most wins in the month of March with 13 heading into the weekend. While not particularly proficient on either end of the floor statistically, they have become a solid proposition each night with players sliding seamlessly into roles that work for them.

Much of that has to do with the return to form of Khris Middleton, a wonderfully underrated player who can shoot, score, and defend. Middleton has brought balance to the Bucks, providing a secondary scorer whenever Giannis is on the court and a primary option when he gets his rest. Kidd has made a point of staggering their minutes so that one of them is always on the floor.

With Middleton back in the lineup, there’s ample shooting around Giannis and dependable size down low, thanks to the revitalized play of Monroe, who should get Sixth Man of the Year consideration. Veteran characters like Terry, Matthew Dellavedova, and Tony Snell provide steady shooting and interchangeable versatility. Brogdon, the aforementioned old rookie, has been both consistent and a revelation all season.

What makes the Bucks unique is they have so much length. Even when they go “small” they are still enormous. All that speed and wingspan creates a chaotic match-up nightmare and all that comes back to Giannis.

Consider the game against the Celtics, who used no less than four different players from all the major position groups to guard him. First it was Al Horford, who at least had the length and savvy, if not the speed. Horford’s other talents directing the defense were wasted on the match-up, however, and after Giannis popped a couple of threes and the Bucks raced out to a 10-point lead, Stevens turned to Jae Crowder. What he gave away in length, Crowder made up for in strength and quickness. The two battled for most of the game, with Smart and Avery Bradley also taking their turns.

As is typical with Smart’s brand of brutalist defense, his encounters with Giannis helped make it a tight, tense contest. It was not the kind of game that lends itself to heroic maneuvers or breathtaking aerial ballets. Rather, it was the kind of game for a young team to prove itself on the road, which Milwaukee did. The Bucks held off a couple of Boston rallies in the fourth quarter and emerged with an important win on the second night of a back-to-back.

Giannis was tremendous, if not dominant, going for 21 points with nine boards, along with three assists, three steals, and three blocks. It’s the kind of line that shows up only a handful of times during the course of the season, made the all more extraordinary by how casual it all was.

In the joyful din of a jubilant young locker room, Giannis offered one more possibility for future.

“Hopefully one day I can be able to lead this team deep into the playoffs,” he said. “And hopefully to the Finals.”

Of such pedestrian pursuits are the most epic tales of Greek mythology born. Giannis Antetokounmpo is crafting his own legend and he’s still just 22 years old. Holy shit.