Sometime within the next month or so, Danny Ainge needs to acquire at least nine more players, determine what to do with his team’s three draft picks, make decisions on the team’s 19 million (approximate) free agents, and formulate a plan for rebuilding, whether that plan begins now or following a year or two in which all of (or most of) the Core Four remain in place as a bridge to the future. Everything Ainge does will be guided by factors he doesn’t control, like whether Kevin Garnett will retire, or whether Ray Allen wants to return, or how much money other teams throw at Brandon Bass. And Ainge has to accomplish all of the aforementioned requirements despite cap space that is anything but fluid, caught up in cap holds at least for now.

Nobody said Ainge’s job was easy. It could have been easier if the 2012 free agent class was everything it promised to be, but Dwight Howard opted out, a few other dominoes fell, and there are no remaining panaceas available on the open market. Ainge’s task now requires a significant amount of creativity, which it probably would have anyway since Howard wearing green was never probable. As Ainge explained Wednesday during a long interview on WEEI, teams rarely rebuild entire rosters in one summer. The Miami Heat are the exception, not the rule. Most teams need to rely on intelligent draft picks and impressive trades to go from one stage in rebuilding to another.

Yes, the Boston Celtics are rebuilding. They might look very familiar next season (or they might not), but they have stopped focusing entirely on a win-now approach. If Ainge can find a way to contend for a title next season, he’ll be thrilled. But he’s more focused on the future now, and has been since two years ago when he began freeing cap space and flexibility for this summer.

Asked whether he expects to renounce the rights to Boston’s many free agents to free cap space, Ainge said it’s not likely.

“It’s unlikely, because they are good players,” Ainge said. “All of those guys are starters, big-time contributors on a good team. And the free-agent market isn’t that great.”

Ainge pointed to sign-and-trades as a real option, saying that cap space often lends itself more easily to trades than it does to actually signing free agents. He is probably thinking about a similar scenario to last year, when he flipped the rights to Glen Davis (then a free agent with the Celtics) for Brandon Bass.

This summer, the Celtics will have similar opportunities for sign-and-trades. Ray Allen, Kevin Garnett and Brandon Bass (and maybe others) are all likely to draw serious interest from around the league. This is where Ainge is his best, when survival requires building a raft of bamboo sticks and powering it with paddles made of leftover materials from the plane crash. Remember last offseason: Ainge parlayed zero cap space and a mini mid-level exception into a bench of Jeff Green, Keyon Dooling, Mickael Pietrus, Chris Wilcox, Brandon Bass and Greg Stiemsma. Green missed the entire season and Bass was thrust by injuries into the starting lineup, but that didn’t change the fact that Ainge turned nothing into something good. If he had somehow also signed David West, which Ainge almost managed, somehow, Ainge would have had one of the best summers ever submitted by an NBA executive.

Ainge’s choices this offseason include retaining Garnett, trying to keep Allen, re-acquiring Bass and Green, and trying another run next year essentially with the team that was supposed to compete this season. Ainge seemed extremely content with the roster the Celtics thought they had to begin last season, but after injuries and heart issues gutted some of the rotation, he felt the team overachieved to make it within one quarter of the NBA Finals.

“I thought where we got — with a chance (to make the NBA Finals) — was expected when the season started, when we looked at our roster and we thought we would have Avery Bradley, Jeff Green, Chris Wilcox, (as well as) Brandon Bass coming off our bench,” said Ainge. “I thought that was a very good team with high expectations. Not only with the three guys (Bradley, Green and Wilcox) that we didn’t have in the playoffs, but Paul (Pierce) and Ray (Allen) were not 100 percent through playoffs and those guys gutted it out and were very gritty. They had some spectacular games, some flashbacks, but in the end we just didn’t have enough.”

“Had we had our 24- (Green) and 21-year-old (Bradley) healthy, we could be in the NBA Finals right now,” said Ainge.

But Allen seems likely to leave, Garnett still hasn’t decided whether to call it quits, Bass will have other suitors, and Green’s agent seems convinced half the NBA will line up to knock on his client’s door as soon as July 1 arrives. The rebuilding process has already begun, but nobody — including Ainge — has any idea where this is headed. This journey will take finesse and cunning, and maybe patience, and it will require chasing down each possibility to see how realistic it might be.

Ainge is in a tough spot. His possibilities are endless, but very few of them, maybe none of them, are home runs. His task is enormous. And you get the feeling that’s the way he likes it.