So, what's next for the franchise cornerstone?
While Paul Pierce and Kevin Garnett's futures are certainly in doubt, Rondo's remains to be seen as well. The 27-year-old point guard is a four-time All-Star but is recovering from surgery to repair a torn ACL.
With plenty of questions left to be answered heading into the offseason, let's take a look at where we stand with the latest chatter surrounding Boston's Rajon Rondo.
Rondo Confident About Recovery
Rajon Rondo has yet to announce a return date following surgery to repair a torn ACL, which he suffered in late January.
Rondo underwent surgery on his knee in mid-February, according to ESPNBoston.com.
When I got out of surgery, for three to four weeks nobody said anything about when I'll be back, or when I'll be able to play. They just wanted me to take it one week at a time and just see how I progress from there Everybody's body is different. Everybody plays the game differently. An injury like this varies.
Two months into his recovery in mid-April, Rondo had no answer for ESPN's Hannah Storm when asked about a potential timetable for a return to the court.
It seems unlikely that Rondo would be 100 percent and ready to go by the start of the 2013-14 regular season, but assuming he can be ready to contribute sometime in early 2014, perhaps the Celtics can avenge their early playoff exit.
After all, Rondo's presence on the floor makes a world of difference for Boston. He's averaged a double-double in points and assists in each of the past three regular seasons and at times makes triple-doubles look easy.
Rondo averaged 13.7 points, 11.1 assists (led the league) and 5.6 rebounds per game in 38 games this past season before being shut down.
Is Boston Still Willing to Part Ways with Rondo?
Prior to last February's midseason trade deadline, the Boston Celtics made Rajon Rondo "available," according to league sources (via ESPN's Chris Broussard.)
Boston Celtics guard Rajon Rondo, who had season-ending knee surgery a week ago, is available for a trade by Thursday's deadline, league sources tell ESPN's Chris Broussard.
However, a trade is unlikely because of Rondo's injury, a torn left ACL, sources tell Broussard.
As expected, the deadline passed without Rondo being moved.
While all is quiet on the Rajon Rondo trade front heading into the offseason, there's the potential for it to pick back up as the summer heats up.
Lakers GM Mitch Kupchak maintained that L.A. was unwilling to part ways with Howard.
At age 27, Rondo is entering the prime of his NBA career. He's a tremendous asset for the Boston Celtics, whether they plan to build around him or deal him in a move to bring in some other young talent.
According to Spotrac.com, Rondo has two more seasons remaining on his current deal and wouldn't become an unrestricted free agent until the summer of 2015.
The Celtics owe him close to $25 million over the next two years.
Boston is facing a handful of questions heading into the summer, especially with Paul Pierce (will turn 36 in October) and Kevin Garnett (will turn 37 this May) in the twilights of their respective careers, but Rondo is the franchise's key piece.
How he bounces back from injury and what the Celtics decide to do with him will determine how the franchise fares moving forward.
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