When Danny Ainge refused to include Jayson Tatum in any trade talks for Anthony Davis, it wasn’t just because Davis was going to be a one-year flight risk.

Ainge was skittish to include other not-so-notable pieces of such a deal like Jaylen Brown and Marcus Smart, as well.

Ainge has had trade proposals of some sort for most of the players on this roster within the last year-plus, and has politely passed on them.

And the reason?

Because this team more than any other except for maybe the 2008 squad and the teams that followed shortly after that group was formed, is a group that Ainge has a tremendous amount of faith in that can be successful and compete at the highest of levels.

But is that faith well-placed or fool’s gold?

Based on conversations with multiple league officials over the weekend, here we take a look at five factors that they pointed out that provide some insight into why Ainge has been so reluctant to part ways with the core players on this team.

YOUTHFUL TALENT

When the Anthony Davis rumors started to circulate and it became clear that he wasn’t willing to commit to the Celtics for any time beyond this upcoming season, that essentially took Jayson Tatum off the table according to multiple league officials.

“I would have been shocked if he (Danny Ainge, Celtics' president of basketball operations) would have done the deal,” one Eastern Conference General Manager told NBC Sports Boston. “Danny loves Jayson. Anytime you talk about his team and the conversation steers towards Jayson, it’s obvious … it would have to be a special, special talent that wasn’t going anywhere for a while to get Ainge to trade him. If Anthony’s people would have been open to him sticking around longer, maybe Danny would have seriously thought about it then. But Ainge when it comes to Tatum … he thinks the kid is going to a special, special player in this league.”

And with Tatum just 21 years of age, he is viewed by most execs as a future all-star who has the potential to be one of the best players in the league for many years to come.

Jaylen Brown doesn’t get that kind of universal love, but he too is a player that Ainge values highly and is “very hesitant” to include any deals that don’t render the Celtics a proven star in return.

Ainge reportedly didn't want Brown included in a deal for Kawhi Leonard who eventually was traded from San Antonio to Toronto, and just last week led the Raptors to an NBA title while claiming NBA Finals MVP for the second time in his career.

At that time, Brown was playing some of his best basketball while there were lingering questions about Leonard's health and to a lesser extent, commitment to the game.

But Brown's struggles to start the season and eventually being shipped to being a reserve, led some to believe Boston was as open as they ever were to moving Brown.

“We tried to engage them on trading for Jaylen earlier this past season when it seemed he had fallen out of favor, wasn’t starting and all that stuff,” said an Eastern Conference player personnel executive. “You go in knowing the asking price will be high at the start; that’s how it is with most teams you’re looking to partner with in acquiring one of their players. But in our conversations with them … they weren’t looking to move Jaylen. The only way that was happening was if it was one of those no-brainer trades where they landed a proven player with star-like talent.”

Another Eastern Conference executive added, “Put it this way. Tatum was what, No. 3 pick? And Jaylen was the No. 3 pick too. Look around the NBA and see how many of those guys get traded while still on their rookie deals. Not many. And if they do, it’s because they suck or the player or players the team receives for them, are really good; like all-star good.”

An NBA scout in the Western Conference said Ainge’s strategy on dealing with his young players is about basic economics.

“Every team wants to get as much bang for their buck,” the scout said. “Look at it from Danny’s perspective for a second. I got a No. 3 pick from two years ago (Brown) and a No. 3 pick from a year ago (Tatum) starting for me in the Eastern Conference finals (in 2018). I got my 16th or 17th or wherever they picked Terry Rozier (16th overall in 2015) starting too.

He added, “I got 60 percent of my starting lineup on rookie deals, and I’m in the Conference finals. That my friend, is tremendous bang for your buck right there.”

CHEMISTRY

One of the reasons why Boston’s youthful players had so much early success, was because of the on-the-floor chemistry they developed.

Remember, Jaylen Brown and Jayson Tatum were like two peas in a pod during Tatum’s rookie season, even prompting some to try and come up with a nickname for the duo.

“Both guys are really motivated to be great in this league,” said the Western Conference executive. “But what really surprised a lot of folks was how well they played off of one another, and how they figured out early on how to develop a healthy competition with each other.”

That chemistry has allowed them to lean on one another during the tough times, like when Brown found himself out of the starting lineup and then trying to establish his niche with the second unit.

And Tatum dealing with the high expectations that many had for him this season and felt he didn’t achieve even though he showed growth statistically in most of the major scoring and defensive categories.

The wild card in Boston’s chemistry experiment going so wildly successful in 2018, was Terry Rozier.

He handled the spotlight in 2018 well in addition to factoring heavily into the team’s postseason success. But this past season was one in which he was back to being more of a backup, a role that he never seemed comfortable with or play with enough consistency.

If he’s re-signed this summer, it’ll be for him to be a starting point guard for this team which, based on his track record, bodes well for him and Boston.

In 30 starts, he has a 22-8 record while averaging 14.4 points, 5.9 rebounds and 4.1 assists per game.

He’s a restricted free agent this summer and will have suitors, although that list might dip some with Kyrie Irving expected to sign elsewhere which would leave Boston a sizable gap at the point in need of being filled.

“All along, I felt if they didn’t get Kyrie they would try and lock up Terry pretty quick,” said the Eastern Conference GM. “We don't know if that's going to happen, but it makes sense. I don’t know his (Rozier) numbers when he started but I know they won most of the time.”

BIG GAME PERFORMERS

One of the biggest concerns with building a team from the ground up, is that young players often wilt under that first initial trial by fire during the postseason.

That’s why the idea of Boston moving past Irving and centering their efforts around a trio of players all 25 years old and younger (Tatum, Brown and Rozier), isn’t as frightening to the Celtics as it might be for some teams with similarly aged players.

“What happened in 2018 was the best and worst thing that could have happened to Boston,” said the Western Conference scout. “Those young guys figured out not just how to play in the playoffs, but win games; big games."

In Boston’s series-clinching win over Milwaukee in 2018, it was Rozier who had a near double-double with 29 points, nine assists and six rebounds.

In the Celtics’ series-clinching win over Philadelphia in the second round of their 2018 postseason run, Brown’s 24 points on 10-for-13 shooting would be part of a stretch in which he had 20 or more points in four of the team’s next five playoff games.

And Jayson Tatum’s dunk over LeBron James was impressive that year, but it wasn’t the only impactful play he made during the postseason.

Against the Sixers, Tatum scored at least 20 points in all five games while averaging 18.5 points per game for the entire Celtics postseason run.

But at least one league executive, while acknowledging what they did in 2018 was impressive, isn’t convinced keeping the core together will produce similar results going forward.

“The landscape looks a lot different now than it did just a couple years ago,” said the Eastern Conference personnel official. “LeBron left but in comes Kawhi. Did that make things easier in the East? Nope. I think all of those Celtics guys will be better; I have no doubts about that. But the same can be said for a lot of teams in the East. I’m not sold on them getting better in Boston being enough to get them back to where they were or further, in 2018.”

Added the Western Conference scout: “The thing is, those guys know that they can show up and win those kind of games. You look around the NBA at guys who are 25 and under, they either have the talent but haven’t gone through that kind of experience. Or they have been on teams that went that far, but didn’t play enough to really know what that’s about, or they played enough and got exposed for not being ready. The Celtics and their young guys, they don’t have that issue as much as others do.”

STAYING HUNGRY, HUMBLE

As the Celtics season steadily spiraled into one of lost opportunity and disappointment, they acknowledged they may have been riding the hype train surrounding their success more than they should.

“They did,” said the Eastern Conference personnel official. “They didn’t play hungry anymore. They didn’t play with an edge, gritty … all the things that got them to where they were, they didn’t do those things as much.”

The Western Conference scout said that the Celtics were too quick to let Kyrie Irving get much of the blame while not enough went to Ainge who put the team together, or head coach Brad Stevens.

“The two biggest influencers on your team are the head coach and the GM or whoever puts the team together,” the scout said. “When the team wins, they should get a lion’s share of the credit. The coach put guys in the right position and the GM gave him the right guys to win with. The same is true when the S#$% isn’t working. A big part of that is that players aren’t put in the right position to be successful, or the coach doesn’t have the right players to put in position, to be successful.

He added, “Kyrie by no means was a saint or blameless this year. But folks act like he put the team together or he was calling plays that didn’t work. Danny and Brad deserve a good slice of the blame pie for this past season, too.”

The consensus among the executives and scouts spoken to for this article, is that Boston’s group will come back with an elevated level of hunger not only because of the way last season ended but also because of Irving’s expected departure and the players looking to prove that 2018 was not a fluke and that they’ve grown from that experience as well as the ups and downs from last year.

“This group knows what can happen when you stay hungry and humble,” said the league executive. “You position yourself to have a season like they did in 2018. But when you lose sight of that even for a minute, things can go sideways quickly and you’re left with trying to deal with what, based on what the players have been saying lately, was a season with a whole lot of behind-the-scenes drama going on.”

One executive pointed out this team needs to take more cues from guys like Jaylen Brown and Marcus Smart.

“Jaylen Brown, Marcus Smart, those guys are dogs,” said the Eastern Conference personnel executive. “And I mean that in a good way; they’re tough, gritty, not to be messed with or pushed around. Boston wasn’t a very tough team last year and I think a lot of that has to do with bad leadership that never really seemed to demand - not hope for but demand - that guys be tougher mentally and physically.

He added, “It’s not going to come from Al (Horford) who is a tough guy but is more about doing his thing by his actions, rather than words. (Aron) Baynes will help but he doesn’t play enough to get the kind of respect a starter or a major rotation player would get. But Brown and Smart, those guys need to step up more this year as leaders.”

COACH-PLAYER FIT

One of the big question marks surrounding the Boston Celtics was whether Brad Stevens could coach Kyrie Irving.

Considering Irving had one of his most efficient seasons ever and was named to the All-NBA second team (a first for Irving), I think the answer to that is a resounding … Hell yeah!

But more significant was whether Stevens could get the most out of Irving while still getting the most out of the surrounding cast.

“That didn’t happen,” the scout said. “It just seemed when Kyrie was at his best, the other guys weren’t. And when they seemed to be playing well, Kyrie was out or Kyrie wasn’t as big a factor. They never seemed to mesh the way many thought they would.”

The Eastern Conference GM declined to speak about the Stevens-Irving dynamic other than to say, “you’re talking about one of the best coaches in the NBA and one of the most talented players. We’ve seen it in past years where things for whatever reason don’t work even when you have two really talented folks who are both focused on success. Placing blame is pointless. The bottom line is that it didn’t work which like I said, is not new when it comes to bringing together talented people.”

But the players likely to return from the core group have shown an ability to be at their best under Stevens which gives hope that with added experience, they can take their games and this team’s chances at postseason success, to another level.

And in doing so, validate the faith Ainge has shown in this group, the kind of faith we haven’t seen from Ainge since the late 2000s when the Celtics were a perennial title contender with a core that by and large remained intact for years.

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