About 15 kids had jumped in the pool during a birthday party at Jameer Nelson’s home. And right in the middle of the action was a college-aged Charlie Brown Jr., the Philly kid and budding St. Joseph’s standout, who was invited by a mutual friend to tag along for the backyard gathering with Nelson’s family and friends.

“He was having a ball,” recalled Nelson, the Chester native and former All-American at St. Joe’s and 14-year NBA veteran who is now the assistant general manager of the 76ers’ G League affiliate, the Delaware Blue Coats. “He was throwing the kids around and enjoying himself. That’s the Charlie I know: humble, passionate about life itself, great kid and comes from a great family.”

Brown is already a feel-good story during this strange NBA season. The third-year pro got the call-up for a 10-day hardship contract with his hometown team when the omicron COVID-19 variant ripped through the Sixers’ roster, then swiftly turned that into a two-way deal. He was plopped into the rotation when fellow Sixers wings Matisse Thybulle and Danny Green were sidelined with injuries and in health and safety protocols, and has since proved to coach Doc Rivers that he is an NBA-caliber defender.

Yet Brown’s opportunity is particularly special for Nelson, who, since those initial meetings, has watched Brown develop with the Blue Coats and is now pulling for him to carve out a more permanent spot in the NBA.

“This is my guy,” Nelson said. “I have a job to do and I have to put the relationship on the side and do my job, but it is what it is. I have a bond with him. I have a relationship. You can’t hide it 100 percent. I’m a former player, and I want to see younger guys succeed. …

“I believe in the kid. I believe that he’ll be a professional for a long time. Hopefully, that’s in the NBA.”

A huge grin crossed Brown’s face when asked if he followed Nelson’s playing career. Though he is too young to remember Nelson becoming college basketball’s national player of the year, Brown tracked Nelson as he played for the Orlando Magic, Dallas Mavericks, Boston Celtics, Denver Nuggets, New Orleans Pelicans, and Detroit Pistons from 2004-18. Brown appreciated the way Nelson thought the game and never let a defender speed up his desired pace.

Up-and-comer

Through Nelson’s continued connection to the Philly Pride AAU club, he learned early on that Brown was a local up-and-comer. Nelson once invited Brown to an NBA practice, where Brown remembers “the things that came out of his mouth, it was legendary.”

“He’s like Chris Paul,” Brown said. “They always talk, but they mean well. You can’t do nothing but listen to them, because they’re only saying good things. That was probably my best part of [watching] his whole basketball career — the way he talked, the way he uses his words and how he brings everybody together.”

Brown also eventually wound up starring at St. Joseph’s — and at that Nelson family party the summer after his freshman season that he fondly remembers.

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“It just made sense to talk to him,” Brown said of Nelson. “… I kind of said to myself, ‘I’ve got to be around him. I’ve got to learn what he’s teaching and just build habits off of him.’ I’ve been doing it this whole time.”

After going undrafted in 2019, Brown got a couple of NBA tastes the next two seasons with the Atlanta Hawks and Oklahoma City Thunder but spent the bulk of his time in the G League. He was initially viewed as a more offensively oriented player, which Nelson, now wearing the hat of professional talent evaluator and roster builder, said made it “hard to fit him in, in my opinion, to an NBA team.”

But the Blue Coats’ defensive style has allowed Brown to flourish on that end of the floor. At 6-foot-6, he has used his versatility to guard positions 1 through 4, his length to jump into passing lanes, and his energy and hustle to stay in front of ballhandlers, rebound, and dive for loose balls.

“The intangibles that he’s shown that he’s capable of doing now, that to me is what opened people’s eyes,” Nelson said. “... Now it’s easier [to envision him on an NBA roster], because the path has changed a little bit, his profile has changed a little bit.”

Brown first got a 10-day hardship deal with Dallas in late December, appearing in three games. But when the Sixers called him up less than a week after that, it was a “dream come true.” When asked which in a flood of congratulatory messages and well wishes from friends and family was most meaningful, Brown paused and said Nelson’s.

Nelson reminded Brown to try to limit the distractions that naturally (and sometimes unintentionally) arrive while playing in one’s hometown. His advice epitomized Brown’s mantra to “stay small.”

“A lot of people try to cling onto you and just ask for a lot, just try to be around you,” Brown said. “[Nelson] just said, ‘Just isolate yourself. Just stay down and work hard. This could turn into a 10-year [career].’

“That’s probably the biggest thing. I’ve been taking that into consideration every day, every minute. I don’t want to lose this opportunity, because it’s special.”

‘One-man zone’

Entering Monday, Brown had played in 12 games for the Sixers since Jan. 7, including two starts. His first bucket was a transition and-one against San Antonio that ignited the home crowd. During a massive Jan. 15 win at Miami, Rivers called Brown a “one-man zone” while he toggled between guarding perimeter standouts Jimmy Butler, Tyler Herro, and Duncan Robinson. He pulled down nine rebounds, including four on the offensive end, less than 48 hours later at Washington. He scored a season-high seven points during a Jan. 23 win at San Antonio while also defending versatile Spurs guard Dejounte Murray. At the end of the second and third quarters of Monday’s wild overtime victory over the Grizzlies, Brown checked in specifically for the Sixers’ final defensive possession of the period.

Those immediate efforts have prompted many Sixers teammates and staffers to join Brown’s corner.

He credits skill development coach Jason Love with providing the film cut-ups that have helped the game slow down. He immediately bonded with backup center Andre Drummond because both players went to St. Thomas More Prep in Connecticut before their college careers. He appreciated veteran wing Danny Green reminding him to stay in the moment when he got frustrated with a foul call during the game in San Antonio. And he got an unprompted shout-out from Rivers before Saturday’s win against the Kings, noting that a positive of the Sixers’ roster instability was that he got a firsthand look at Brown’s potential.

“He’s very receptive. He’s been great at it. He’s figuring it out,” Green said of Brown. “For a guy that’s been here for like three weeks, he’s done an amazing job and given us a big boost of energy on [the defensive] side of the floor and making some big plays that help us down the stretch.”

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Brown’s minutes diminished after Thybulle and Green returned from injury late last week. He went back to Delaware to get some game run with the Blue Coats on Sunday, totaling 21 points on 6-of-10 shooting (including five three-pointers) and five rebounds in a 131-95 victory against G League Ignite.

And after a month of regular check-ins by phone, Brown’s brief return to Wilmington also provided the opportunity to catch up with Nelson in person.

“He uses his words wisely,” Brown said. “He doesn’t really waste time trying to beat around the bush. He’s a straightforward person and he’s an honest person. He’s a genuine person. I would love to have that in my circle, and I do have that in my circle.

“So I’m not going to take [it for granted]. I’m going to keep listening to what he’s saying and stay in his ear.”