BOSTON -- The day after one of the most memorable seasons in Boston Celtics history ended last spring -- and that's saying something, considering it was one in which the Celtics didn't raise a title banner -- Boston players gathered at the team's training facility, where one question hovered like a fog amid the 17 banners that ring the practice floor.
How could the Celtics close the gap with the Cleveland Cavaliers?
As enthralling as Boston's season was, spearheaded by a 5-foot-9 Isaiah Thomas transforming himself into an All-NBA player before a balky hip could take no more, the Celtics had been swiftly and unceremoniously bounced from the Eastern Conference finals in five games by LeBron James & Co.
The divide between the teams was evident, and it was clear the Celtics needed more than minor tweaks to get over the Cleveland hump. So when Al Horford stepped before a group of reporters at Boston's breakdown day, less than 24 hours after the Celtics' season ended, he balanced appreciation for the season with obvious uncertainty about what was ahead.
"We've had such a good year. A lot of positive things, but it will be interesting to see what Danny [Ainge] and the organization feels is going to be the next step," Horford said.
We know now what the Celtics did: They tore apart a team that won 53 games and earned the No. 1 seed in the East. They boldly traded the No. 1 pick in the draft, confident they could get their guy and add a pick who would contribute to a brighter future. They landed the biggest fish in the free-agent pond. Then they shocked the NBA by trading Thomas to those rival Cavaliers in a late-August blockbuster.
These new-look Celtics -- only four players remain from last year's team -- are headed back to the East finals for another date with the Cavaliers after a 114-112 triumph over the Philadelphia 76ers in Game 5 of a semifinal series Wednesday night at TD Garden.
So much has changed, for both the Celtics and the Cavaliers, even since the start of the season. Cleveland dealt away Thomas as part of a massive midseason roster overhaul, while a young Boston squad has persevered through a relentless injury bug that feasted on Gordon Hayward on opening night, then returned for Kyrie Irving later in the season.
But for a new roster, the same question remains: Have the Celtics narrowed the gap with the Cavaliers?
It's kind of wild that we're even talking about a Celtics-Cavaliers matchup in the East finals. There were times throughout the season when neither team seemed destined to represent the East.
Five minutes into Boston's opening-night matchup in Cleveland, Hayward came down awkwardly while trying to corral an alley-oop feed from Irving, and his ankle bent awkwardly as he crashed to the floor. Computer models that pegged the Celtics to win the East adjusted them to a .500 squad pegged to finish in the middle of a crowded East.
The Celtics instead embarked on a 16-game win streak early in the season, asserting themselves as contenders even without Hayward. The injury bug returned late, and during a March 11 game against the Pacers, Boston lost Irving, Marcus Smart and Daniel Theis for the remainder of the regular season.
Even as few outsiders expected Boston to stick around long in the postseason, Horford had faith in his young teammates.
"I've seen the way these guys prepare," Horford said after the Game 5 victory Wednesday. "They want to be great and they understand it's bigger than them. It's about the team and you have to do things the right way. The way they prepare and the way we've been so resilient all season, it doesn't surprise me at this point."
Smart returned in Game 5 of the Celtics' first-round series against the Milwaukee Bucks and helped the team grind out a win in seven games. A rally from 22 down in Game 2 against the Sixers helped Boston dispatch The Process in five games.
Yes, the Celtics managed to find ways to limit the impacts of Giannis Antetokounmpo and Joel Embiid. But now they must find a way to do what no team in the East has done since the Celtics in 2010: beat LeBron.
But will young players like Tatum, Brown and Terry Rozier continue to thrive for Boston?
"Obviously guys have been going down all year, it's like you never know who's going to go down, things like that, but we find a way," said Rozier, who has shined as the team's starting point guard since Irving was lost for the season. "We pull together. I'm not saying we're better or not [than last year's team], but we're definitely going back to the Eastern Conference finals, and that's a blessing."
How much have things changed in Cleveland? Four of the 10 players from its opening-night rotation are no longer with the team. Gone are three starters: Jae Crowder and Derrick Rose went to Utah for Rodney Hood, and Dwyane Wade was dealt home to Miami. Plus, Iman Shumpert went to Sacramento in exchange for George Hill.
The new-look Cavs throttled the Celtics in Boston in early February -- on a day when Paul Pierce's No. 34 went to the rafters, no less -- but things rarely went smoothly for the Cavaliers on their way to settling for the No. 4 seed in the East.
And yet, even after looking vulnerable against the Pacers in Round 1, the Cavaliers seemed to ratchet up their game with an absolutely ruthless sweep of the top-seeded Raptors.
The Cavaliers have won five consecutive games and seven of their past eight to reach the conference finals for the fourth straight year.
"We've had four or five seasons wrapped in one. We've talked about it all year. We know what the narrative has been about our team," James said. "But I can only speak in the moment. To be able to put ourselves in position where we can represent the Eastern Conference in the Finals, that's all you can ask for. So we're excited about being part of the Eastern Conference finals once again and having the opportunity to compete for a championship.
"That is what our goal is. We're excited about that."
James' supporting cast, lampooned recently in an unaired skit on "Saturday Night Live," might finally be finding its groove. After only two players averaged double digits in the first round against Indiana, six did so in the conference semifinals against Toronto.
"We talk about, through the whole course of this long season, just getting better, getting better. Hitting our stride when the playoffs start," Cavaliers coach Ty Lue said. "And the guys, we're getting a lot of different contributions from a lot of guys. We got a lot of guys playing well, good team effort.
"We got to continue to keep getting better. We talked about that just throughout the playoffs: getting better and finally hitting a good rhythm."
Have the Celtics closed the gap on the Cavaliers? The question won't have an answer until we see these Celtics at full strength, but coach Brad Stevens won't let his team use the absences as an excuse for not being more competitive than last year's Eastern Conference finalists were.
The Celtics made their offseason moves without any guarantee that the moves would make for a better team. But even through all the adversity, you can see the potential of this squad. Boston has a very bright future, but as this season has proved, these players don't want to wait to be great.
"After Gordon, Kyrie, Marcus and Theis went down, no one expected us to go to the Eastern Conference finals," Tatum said. "We just continue to prove people wrong and have fun while we're doing it."
Rozier had a little fun when he was asked what's going to happen in the next round. He smiled and offered a bit of advice.
Said Rozier: "Stay tuned."