PHILADELPHIA — Moritz Wagner’s first impression of life in the NBA taught him a valuable lesson.

Wagner, a 2018 first-round draft pick by the Los Angeles Lakers, had practiced only a few times in his new city before he saw teammate Thomas Bryant get waived. Wagner and Bryant had played against each other for years and had developed into promising centers while rivals in the Big Ten Conference. Wagner knew the beast Bryant could become, but suddenly the Lakers were getting rid of him after only one season.

“First of all, the league is crazy,” Wagner said. “I remember that was one of my first practices, and Thomas got cut. I was like, ‘What’s going on here?’ It was just like my welcome to the league.”

Wagner’s rocky 2018-19 season started with that moment, and it didn’t improve much. Wagner spent much of his rookie year in the G League before he, too, was cast away by Los Angeles after one year, via a trade to Washington so the Lakers could make room for the salary of new addition Anthony Davis.

Adding salt to the wound, Wagner, who’s from Berlin, was left off the German national team for the FIBA World Cup. Wagner said it was the first time in his career that he did not make a basketball team.

“Hey, man, sometimes stuff just doesn’t work out,” he said. “So it was a weird feeling at first, but it was a blessing. There was a silver lining in a sense of that I could move to D.C. earlier and kind of get used to everything and kind of get a head start on training camp, be fully healthy and just mentally get locked into one thing.”

Just 22 as the start of his second pro season nears, Wagner already has learned how unforgiving big-time basketball can be.

“I kind of understand you need to fall down to stand up and get better,” he said. “It hasn’t always been going the way I wanted it, and it would be weird if it went [well] right now because it’s never went that way. So I’m cool with it.”

The Wizards’ preseason results mean little, but Wagner seems set to establish himself in the NBA. On Friday, as the Wizards won their finale, 112-93, at the Philadelphia 76ers — who played their normal rotation sans Ben Simmons (back) — Wagner backed up Thomas and finished with 14 points on 6-for-9 shooting in 12 minutes.

During a four-minute stretch in the second quarter, Wagner matched up with all-star center Joel Embiid: He scored on him twice (with a spin move in the paint and a catch-and-shoot three-pointer) and drew a charge. Wagner also moved well without the ball, often diving to the rim or popping free beyond the arc after setting a screen.

Wagner left the game with 1:03 remaining in the third quarter after taking a Flagrant 1 foul from Embiid. Wagner drove past the big man but absorbed contact while in the air and fell to the court. He grabbed his tailbone and winced in pain, then exited the floor with the trainer and did not return.

Friday’s scare notwithstanding, Wagner averaged 15.8 points in the preseason.

“He’s really gaining some confidence, I think, out of this exhibition season,” Coach Scott Brooks said recently. “I don’t think he had a lot last year. I want him to continue to play with that confidence.”

If last year rocked his self-belief, Wagner hasn’t showed it. During a recent practice, he trapped Rui Hachimura in a bad position beneath the rim and stuffed his shots twice. After sending the second one out of bounds, Wagner barked at the rookie, “Gimme that s---!”

That wasn’t an isolated outburst, according to a teammate who knows him well.

“He always had a lot of energy,” said Isaac Bonga, a rookie with Wagner in Los Angeles last season before both came to Washington in the summer trade. “I mean, obviously he likes talking s--- on the court. He’s always been like that, but I like it, and he’s never going to change.”

Bonga, also a German, predicted Wagner will use the national team snub as motivation in his second NBA season. Regardless, Wagner already has taken the slight as another lesson.

“The one thing that I learned out of this thing,” he said, “and it keeps coming to me, is that if you do the simple things right, life is going to reward you.”

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