Amid the fallout from the Isaiah Thomas-Kyrie Irving blockbuster swap, we keep coming back to something Danny Ainge said almost immediately after Irving's Cleveland Cavaliers ousted Thomas' Boston Celtics in the Eastern Conference finals three months ago.

"I know that we're good. I know that we're not great. I know that we still have more to do, and, you know, that next step is by far the hardest," Ainge told the Boston Herald in late May.

"We have a lot of good players, but we need some great ones." Cavs, Celtics complete blockbuster Three months after meeting in the conference finals, the Cavs and Celtics completed an unprecedented swap of All-Star guards, sending Kyrie Irving to Boston and Isaiah Thomas to Cleveland.

• Woj: Cavs get late pick to complete deal

• Lowe: Why deal makes sense for Boston

• Celtics' focus shifts to roster puzzle

• Post-Kyrie Cavs grasp renewed options

• Forsberg: Boston better after trade?

• The stats behind the star swap

• LeBron takes high road on Twitter

• Vote: Which team won the trade?

• How deal changes East chase | Grades • Marks: Trade's financial impact on Cavs

Most general managers of a team that won 53 games and advanced to the conference finals would be content to add a top draft pick, bring back the core of their roster and roll the dice again the following season.

All Ainge did was trade the No. 1 pick then aggressively pursue the top available free agent while knowing full well signing him would mean a rather aggressive overhaul of the team's roster. And on the very day the Celtics made the signing of that marquee free agent (Gordon Hayward) official, Ainge wouldn't commit to being done with his roster tinkering.

"I don't think that we're ever all set," Ainge said in July. "I think we'll continue to try to get better. Even Golden State and Cleveland are still trying to get better. Every team is trying to get better. We'll continue to look for opportunities."

Opportunity arrived when Irving expressed a desire to get out of LeBron James' shadow. Ainge, sitting atop his well-preserved mountain of future draft picks, pondered the state of the Celtics' roster and elected to tinker again.

But why exactly did Ainge pick Irving as the player to finally push so many of his chips to the center of the table? Garrett Ellwood/NBAE/Getty Images

"We have a lot of good players, but we need some great ones."

For the better part of the past 2½ seasons, the Celtics thrived on a chip-on-their-shoulder mentality personified by Thomas and Jae Crowder, a pair of second-round picks who emerged as the core of Boston's scrappy young team after finally getting a chance to show what they were capable of.

The Celtics were a group of lovable overachievers, a team that coach Brad Stevens seemed to squeeze every ounce of talent out of while its win total climbed. Crowder morphed from part-time role player to a key two-way threat, all while re-signing to one of the league's most agreeable contracts. Thomas, underpaid on a four-year deal he inked with Phoenix, went from a sixth-man spark plug to a top-five finisher in last season's MVP voting.

But as endearing as the Celtics were, there was always the question of just how far away they remained from true title contention. There was an obvious gap between the Celtics and Cavaliers after the East finals, then the Golden State Warriors throttled Cleveland in the title fight.

Ainge did what many others would struggle to do: He divorced the emotional attachment to his players, ignored their recent successes and determined that there simply wasn't enough pure talent to take this team where it desired to go.

Ainge has been aggressive in pursuit of players before but sometimes pulled back before giving up too much. The Celtics tried to smother the Charlotte Hornets with draft picks to land Justise Winslow in the 2015 draft. Boston made aggressive offers in pursuit of players such as Jimmy Butler and Paul George in the 18 months before each was moved this summer.

But in Irving, Ainge saw a 25-year-old with his own chip on his shoulder (and an NBA championship on his resume). Ainge saw a player who might further flourish as an alpha in Boston because he'll be relentlessly motivated to show exactly why he left the King's side.

The Celtics paid a hefty price tag, one that depletes their current depth and stripped key future assets. But that is the price of getting the sort of star talent the Celtics believe is necessary to make that next leap forward. Remember, Ainge said this was the most difficult step.

Boston now has only four players from last season's 15-man roster, in Al Horford, Jaylen Brown, Marcus Smart and Terry Rozier. That's four former first-round picks, including three lottery selections (Rozier was picked 16th after Boston slid out of the lottery when Thomas helped ignite a feverish second-half surge after arriving in February 2015).

Boston, once fueled by those second-round overachievers, is now positioned to trot out a starting lineup gushing with lottery talent. A comparison of last season's starting five by draft position versus this season's potential lineup, with draft position in parenthesis:

How Revamped Celtics Lineup Compares Position 2016-17 2017-18 Point guard Isaiah Thomas (Pick No. 60) Kyrie Irving (1) Shooting guard Avery Bradley (19) Jaylen Brown (3) Small forward Jae Crowder (34) Gordon Hayward (9) Power forward Al Horford (3) Marcus Morris (14) Center Amir Johnson (56) Al Horford (3)

That's all while bringing Smart (6), Jayson Tatum (3), Rozier (16) and Guerschon Yabusele (16) off the bench this season.

To be certain, draft position does not dictate the overall success of a player. Thomas was a legitimate MVP candidate last season and earned his spot on the All-NBA second team with one of the most mesmerizing offensive seasons in Celtics history.

But Ainge yearned for a roster with a higher ceiling, players with a better chance of turning Boston into that true title contender.

There's a case to be made that the Celtics have ultimately upgraded themselves at both the point guard and small forward positions this summer. That's not a knock on Thomas and Crowder, who were spectacular, but the Celtics simply believe that Irving and Hayward are more likely to further expand their game and maintain that level of play deeper into the future.

Celtics co-owner Wyc Grousbeck, addressing reporters after a topping-off ceremony at the pristine new practice facility that Boston will move into next spring, echoed Ainge's declaration when asked about the big-splash move of adding Irving.

Saying goodbye to fan favorite Isaiah Thomas won't be easy in Boston. Winslow Townson/USA TODAY Sports

"We want this team to go for Banner 18 and we needed to get the best possible players to do that," Grousbeck said.

That doesn't make the trade any easier for Celtics fans to digest. It's impossible to overstate just how much Thomas endeared himself to Boston fans over the past 30 months while emerging as the face of the franchise. His size and story made him that much more of a fan favorite, and his No. 4 jerseys were all over TD Garden during Boston's playoff run.

The day after the Celtics were eliminated from the postseason, Thomas held his final group media session with Boston reporters at the team's practice facility in Waltham, Massachusetts. The last question asked was whether he saw a long-term future in Boston.

"I would love to be here long term and win championships here, but, as you guys know, it's a business and anything can happen," a prescient Thomas said.

The NBA can be a ruthless business. Thomas didn't just produce a magical season, but he played through the unimaginable grief of his sister's tragic death on the eve of the 2017 playoffs to lead the Celtics to the East finals, while battling the hip injury that would eventually end his season.

Thomas could have stomped into Ainge's office this summer and, given that the team had ample cap space, demanded to explore a big-money extension. Instead, he encouraged the team to go chase the biggest free agents on the market. Thomas even trekked to Boston to join the sales pitch to Hayward, selling him on how being a star for the Celtics can change your life.

Ainge wouldn't divulge details of his call to Thomas on Tuesday but stressed how difficult that conversation was. At the end of the day, Ainge is paid to put the best possible product on the floor and determined this was Boston's best path forward.

And it all circled back to what he said in late May.

"We have a lot of good players, but we need some great ones."