The three players' injuries—Rondo (ACL), Sullinger (back surgery) and Olynyk (plantar fasciitis)—will impact Boston's future more than just this season, so the Celtics will conceivably take their time in returning their players to the floor.
Ahead is the projected timetables for when fans can expect Boston's injured players to be back on the hardwood.
With Paul Pierce and Kevin Garnett ousted to Brooklyn, Rondo has become the franchise player, leading the team on and off the court. Aside from the heavy load of carrying the team through a rebuild, Rondo also faces a lengthy return from ACL surgery.
On July 20, according to Chris Forsberg of ESPN Boston, Celtics president of basketball operations Danny Ainge speculated that Rondo's return could be opening night, while Pierce noted Rondo is "probably not going to be back until probably December, January, who knows?"
"He's back working out again and hopefully he'll be back by December," said Sullinger.
But that's the closest we've heard to a firm deadline for the star point guard's return to the floor.
On September 5, Ainge met with Bill Simmons of ESPN and Stevens sat down with Kyle Draper of CSNNE.com, but neither provided any further insight into when Rondo could be expected back to full-contact drills.
Per ESPN Boston's Forsberg, who passed along this bit of the Ainge interview:
I'm not sure [when Rondo will be back]. Rondo was working out [Tuesday] with all the guys. He's not near 100 percent yet, but he's out doing shooting drills and ball-handling drills. I really don't have a date yet. We want to be careful with him, obviously.
Stevens wasn't able to provide any other insight on Rondo's return, either.
He's been very diligent when he's been in town. ... I'm the furthest thing from an athletic trainer or doctor, so I don't know about a timeline.
Estimated return date: Tuesday, December 10, 2013
One of the bright young pieces from the 2013 campaign, Sullinger, proved that predraft red flags should be a cause for concern.
ESPN's Chad Ford noted before last year's draft that NBA doctors had medically flagged the power forward due to concerns that Sullinger's back issues could shorten his career. Sullinger's stock plummeted to the Celtics, who snagged him at No. 21 overall.
His season was ultimately cut short due to surgery to repair a lumbar disk in his back, but according to Gary Washburn of The Boston Globe, Sullinger said he is well on his way back to full health.
I've been ready [for training camp], just give me about two more months to be a little smaller. I've been cleared to play. I've been cleared to have contact so I will be ready by Sept. 30.
Keeping the back healthy is Sullinger's ultimate goal and something the first-round pick can continue to do.
According to Washburn, Sullinger has special back exercises that he must perform in order to keep his back strong and continue a healthy career in the NBA.
Estimated return date: Training camp
After impressing at the Orlando Summer League, Olynyk faces the struggles of transitioning into the professional game at the NBA level. He'll also have an injury he hopes to overcome before the season kicks off.
Eric Smith of Sportsnet.ca broke the news on July 29 that Olynyk, who was slated to compete for the Canadian national team, would sit out the summer while recovering from plantar fasciitis, a brutal foot injury for a big man.
A day later, Baxter Holmes of The Boston Globe confirmed from a source that the injury is, "Nothing too serious, but he just needs to rest and recover."
After a local event with the Celtics Shamrock Foundation, Chris Forsberg of ESPN Boston caught up with Olynyk, where the forward/center broke down his injury and what he's doing to get back on the court.
In the interview with ESPN's Forsberg, Olynyk noted that the injury likely flared up after his performance in the summer league and that it was something that had been lingering.
"[The plantar fasciitis] is improving," said Olynyk. "I just have to keep working to get it better every day, doing things I can do. The [team] doctors here have been great. I just need to keep working to be ready for season."
Estimated return date: Training camp
For the Celtics, it won't be necessarily getting everyone into the rotation on opening night, but rather closing the season with these three key players and other young standouts healthy.
If Rondo, Sullinger and Olynyk make it through the strenuous 82-game season unscathed, it might not be much of a rebuild before the Celtics take their place back in the postseason.