It wasn’t that the coaching staff was unaware of these issues, according to team sources; it was that they really didn’t know what to do about it. Without a coach with any real influence on players such as Irving, or who commanded the reverence of younger players, the staff was essentially left helpless to cure the problems.

It became apparent throughout the season that there was major friction among the Celtics players because of some of their understandable personal agendas and how playing time and roles were distributed.

Brad Stevens fell on the sword after the Celtics’ disheartening and humiliating elimination from the Eastern Conference semifinals — as he should have. As much as there is major fault with Kyrie Irving and Gordon Hayward , among others, on the roster, Stevens needs to take this summer for some soul searching on how to move forward. How he builds his coaching staff, approaches his players.

Stevens, who has allowed the players to police themselves in the past, swooped in too late to solve the issues. Some players blamed him for integrating Hayward into the starting lineup without giving more regard to the feelings of Jaylen Brown and Jayson Tatum. And a series of players-only meetings, even one before Game 5, according to the team source, did nothing to solve the on-court problems, resulting in that embarrassing 116-91 loss to the Bucks.


An hour after the Celtics lost Game 5, assistant coach Micah Shrewsberry announced he was leaving the club for an assistant position with his alma mater, Purdue. So there is a position open and Stevens needs to stray from hiring someone from the Butler tree and bring in a veteran NBA coach and former player.

That coach needs to be in tune with the players, who in today’s NBA have a high regard for coaches who played in the league and have experienced what they experience. The Celtics lost a lot when Walter McCarty decided to take the Evansville University job after last season. He was a calming influence and believe it or not the players recognized him not only from his 10-year NBA career but his role in the movie “He Got Game.”


Stevens has loaded his staff in past years with Butler disciples, young coaches skilled in analytics but not necessarily how to handle millennial NBA players. One coach that may have helped the Irving transition to Boston is ex-Cavaliers assistant Phil Handy, who was close to Irving in Cleveland. He was hired before last season by Nick Nurse with the Raptors.

Another coach who is available is former Celtic James Posey, who won two NBA titles (with the Celtics and Heat) and another as an assistant coach with the Cavaliers. Posey, 42, is considered a player-friendly coach but who has a no-nonsense style.

Related: The Celtics have roster issues to deal with. Here’s a closer look

Stevens needs to make some calls to get tips on the best coaches. He needs to compile a list of competent coaches who can add wisdom to the staff, tell stories, and serve as a big brother figure to the players. There’s a reason why veteran coaches fill their staffs with other veteran former NBA coaches. Those coaches can reach the players, can sense issues, and also offer advice and discipline.


It’s not entirely Stevens’s fault that team unity went south this season. He has usually been successful with his hands-off approach, but then he had McCarty as a go-between. This year’s staff was a bunch of good, hard-working guys, but sometimes that’s not enough.

President of basketball operations Danny Ainge should be held responsible also. He has surrounded himself with longtime friends and analytics people who know the game but their strength isn’t necessarily people skills.

Stevens needs some fresh faces on his staff and Ainge needs to add a recognizable face to the front office staff. There are plenty of interested parties who would love to work with the Celtics, former Boston players and others who admire Stevens’s coaching acumen and would love to contribute.

Related: Celtics’ Big Three of blame: Kyrie Irving, Brad Stevens, Danny Ainge

What happened this year was a disaster and it would have been avoidable if it was detected early enough. But no one on the coaching staff felt the empowerment to really deal with high-priced, big-personality players such as Irving, who respected the staff but wasn’t exactly going to listen to a third assistant’s advice on how to cope in the NBA.

There is an opportunity for Stevens and Ainge to make this right, to add some impactful coaches and front office executives to an organization that needs a makeover. The players need someone who they can confide in, can relate to, and hear war stories from. Stevens has succeeded, for the most part, with his previous method but it’s time for change and that should be his No. 1 priority.


NO REGRETS

Johnson relishes time with Bucks

Marques Johnson played for the Bucks from 1977-84 and is now a TV analyst for the team. His number was retired in March. Morry Gash/AP/Associated Press

All-time great Marques Johnson had his No. 8 retired by the Bucks in March. His perspective on the honor, 35 years after he was traded by Milwaukee to the Clippers, was touching. Johnson was a finalist for the Naismith Memorial Hall of Fame this year and is finally getting the respect he deserved for years.

“It’s been great and I’m really grateful to the Bucks,” he said. “A lot of people are like, it took them long enough and they should have done it years ago. But I was never one to embrace the Milwaukee community when I was a player. I’d get out there on the first thing smoking one day after the season ended.

“I was packed up, ready to head back to Los Angeles and to chase fame and fortune and Hollywood and all of that. Sidney Moncrief and I were talking about this and he was talking about how when he got his number retired, he appreciated it but probably would have appreciated it more if more time had passed.”

Moncrief’s No. 4 was retired by the Bucks the year after he retired in 1988-89, but he ended up signing with the Hawks a few months later and played a season in Atlanta before retiring again.

“It feels good because Milwaukee meant so much to me in terms of my formative years as a man, developing as a young man, a 21-year-old coming out of LA and I had no clue what [Milwaukee] was going to be about,” Johnson said. “I didn’t like it initially. But came to really appreciate the genuineness of the people in the Midwest and how they complain about the cold and the winter like they’ve never experienced it before but they’re not going anywhere. That’s what I came to really appreciate. Once I came back at 59 years old and I had a chance to see it from a different perspective, I have enjoyed Milwaukee. The people have truly meant a lot to me. This has been a culmination of all of that.”


Related: He’s watched Antetokounmpo and Middleton turn Bucks into a power

Johnson said he is not one of those former players who bristles over the new NBA rules, such as the gather steps or players being allowed to carry the ball or the lack of physicality. It’s because he’s had a generation of basketball-playing children, such as Kris, 43, who was an integral part of the 1995 UCLA national championship team, and 19-year-old Cyrus, who just finished his freshman season at Sam Houston State.

“I’ve see them working on different aspects of the game in terms of skill level, so I’ve got to be up on the latest of what you can get away with,” Johnson said. “And so now it’s the in-and-out dribble. Back in my day it was a carry. You couldn’t cup the ball on the outside and take it in and take it back out. I showed my 9-year-old daughter that move and she loved it.

“Because I’ve had to stay up [on the changes] as a broadcaster for Fox Sports for 20 years, doing Pac-12 stuff and now doing the Bucks. It’s not like I sat there and the game’s passed me by. I got to practice. I love going through skill development sessions. I was with Pete Newell in the movie “Blue Chips” when he was working out Shaquille [O’Neal], and on a daily basis on set, he was teaching them little hesitation dribbles where you actually had to cup the basketball a little bit and do some things back in the day that were illegal.

“I was like, ‘Pete, that would have been palming back in the day,’ and he was like, ‘Yeah, but they let guys get away with that now so I’ve got to teach the big guys.’ ”

Johnson remembers playing in Jesse Jackson’s Operation Push Charity Game in Memphis in 1982 when he saw Isiah Thomas was doing hesitation dribbles that he said he had never seen before.

“That’s when I first got the idea that the game was kind of changing,” Johnson said. “I don’t get into, ‘Back in my day we couldn’t do this or this.’ I was at my daughter’s game this weekend and one of her teammates took three steps and they called travel and I told the ref, ‘That’s a gather!’ And he looked at me and laughed. When I work with young people, I embrace it. This is what you’ve got to do because this is how the game is played. The game is constantly evolving. They used to say Dr. J [Julius Erving] was traveling because he would take one dribble and then take those two huge steps and take off from the free throw line, but he wasn’t traveling.”

ETC.

Middleton will have many suitors

Khris Middleton averaged 19.2 points per game in the Eastern Conference semifinals against the Celtics. Barry Chin/Globe Staff/Globe Staff

Celtics fans have seen enough of Khris Middleton, who continued his mastery of the Boston defense in the just-concluded Eastern Conference semifinals and was one of the key reasons the Bucks are the favorites to reach the NBA Finals.

But who is this guy? Middleton’s ascension is one of the undertold stories in the NBA, a second-round pick who was a throw-in in a trade for former first-round pick Brandon Jennings. He has now emerged as one of the league’s better shooters and is expected to opt out of the final year of his contract and become an unrestricted free agent.

With Malcolm Brogdon a restricted free agent, the Bucks will have some major decisions this summer. As much as George Hill dominated the Celtics, he’s getting paid handsomely for his services, earning $19 million in the final year of his contract next season. Eric Bledsoe just signed a four-year, $70 million extension this season, while Tony Snell is owed $23 million over the next two years.

The Bucks own Middleton’s Bird rights but are going to have to open up the pocket book to keep him long term. It’s a long way from Fort Wayne of the G-League, where Middleton spent a good chunk of his rookie season with the Detroit Pistons affiliate before the July 2013 trade.

“I wouldn’t say that I had a confidence problem in my early years but I found a way to get better, to get more consistent,” he said. “That comes with experience — that’s mainly the thing I’ve been using now is experience in the situation that I’ve been in.”

Middleton was an immediate starter once he joined the Bucks before the 2013-14 season. He has emerged as one the league’s most consistent perimeter shooters. Middleton is a career 46.1 percent shooter in 28 playoff games, including 61 percent in the Bucks’ seven-game series with the Celtics last season.

A testament to the Bucks’ dominance over the Celtics was that Middleton actually struggled in the final two games of the series, going 9 for 34 from the field and 4 for 16 from the 3-point line. Yet Milwaukee still won both games with ease.

But the Bucks will need Middleton at his best if they plan to win a league championship, which is a realistic goal considering how easily they have disposed of their two playoff opponents.

“This is what you work for, so I guess you can say this is what you imagined in some way or form,” Middleton said of his success. “This is the spot that you work for, to be as a basketball player.”

The Bucks’ roster could be considerably different next season with Nikola Mirotic and Brook Lopez becoming unrestricted free agents. Perhaps the biggest bargain on the roster is Arlington native Pat Connaughton, who is earning $1.64 million this season and $1.7 million next year as part of the two-year deal he signed in the offseason. Connaughton was one of the key players in the Bucks’ domination of the Celtics.

Brogdon, a former second-round pick who earned Rookie of the Year two years ago, should earn a hefty raise from the $1.5 million he made this season. The Bucks will have the right to match any offer. It would be difficult to envision Milwaukee having Hill ($19 million), Bledsoe ($15.6 million), and Brogdon (perhaps $10 million) all on their roster next season in addition to the $25 million Giannis Antetokounmpo earns and then a new contract for Middleton.

Layups

For all of those disappointed Celtics fans, the offseason begins immediately with the draft lottery Tuesday. On that night, the Celtics will see where they draft with the Sacramento pick and whether they will own Memphis’s protected pick (No. 1 to No. 8) or if that pick moves to the 2020 draft. Depending on the depth of the draft, the Celtics could nab a very talented player with the Kings pick. They also own the 20th pick (Clippers) and their own pick at 22. If they want, the Celtics could get considerably younger with their draft picks or use them to trade for veterans. This is what happens when you make so many deals to acquire future first-rounders. Eventually the future arrives . . . Another interesting development for the Celtics is the contract extension talks of Jaylen Brown, one of the few NBA players who doesn’t have an agent. Brown has hired consultants in the past to help him with the business issues of basketball but he would not promise that he would hire an agent for negotiations. He said he will talk with the Celtics, perhaps exchange numbers, and then determine whether he will hire an agent . . . An interesting free agent on the market will be former Celtics guard Rajon Rondo, who played well with the Lakers this season. He missed 36 games because of various injuries but Rondo averaged 8 assists and shot 35.9 percent from the 3-point line, making him an actual perimeter threat. Rondo could be a perfect fit for a team seeking a backup point guard and it’s likely not going to be the Lakers considering the chaos on that team this season . . . The drama in Los Angeles continues as the Lakers were unable to reach agreement with former Cavaliers coach Tyronn Lue on a deal after they offered a three-year contract rather than the usual five-year deal. Celtics coach Brad Stevens received a six-year deal when he agreed to leave Butler in 2013. So considering Lue won an NBA title and reached two other Finals, it’s understandable he was upset about a three-year contract, especially since he is still getting paid by the Cavaliers and would like a deal to exceed that money.