Mired in a six-game losing streak and up against the Miami Heat on Sunday afternoon, the last thing the Boston Celtics needed was to see an impact player go down with an injury.

UPDATE: Wednesday, Feb. 13, at 12:18 p.m. ET by Alex Kay

Rajon Rondo underwent successful surgery on his ACL this Tuesday, performed by the world-renowned James Andrews.

According to Gary Washburn of the Boston Globe, Boston Celtics GM Danny Ainge confirmed there was no further damage to the superstar point guard's knee.

---End of update---

UPDATE: Friday. Feb. 8, at 7:03 a.m. ET by Brandon Galvin

Rajon Rondo will miss six months following knee surgery, according to Yahoo! Sports' Marc J. Spears.

Danny Ainge tells Globe Rondo underwent ACL surgery Tues Performed by James Andrews. Ainge says Rondo suffered no other knee damage #celtics

— gary washburn (@GwashNBAGlobe) February 13, 2013

---End of update---

UPDATE: Monday, Jan. 28, at 6:23 p.m. ET by Tim Keeney

While hope for this season may be dwindling, Danny Ainge offered some encouraging news regarding the Boston Celtics' star point guard (via the Boston Herald's Mark Murphy):

Though the recovery from reconstructive knee surgery can vary, depending on the player, Ainge said he expects Rondo to be ready for the start of training camp next season.

Ainge said Rondo should undergo surgery in the next "10 to 14 days."

---End of update---

UPDATE: Sunday, Jan. 27 at 2:36 p.m. ET by Brandon Galvin

Awful news for Celtics fans, as ESPN's Doris Burke announced on ABC during the Heat vs. Celtics game that Rondo did tear his ACL, according to WEEI.com's Mike Petraglia. 

Celtics G Rajon Rondo projected to be out 6 months after surgery next week to repair a partially torn right knee ACL, a source told Y! Spors

— Marc J. Spears (@SpearsNBAYahoo) February 8, 2013

---End of update---

UPDATE: Sunday, Jan. 27, at 2:15 p.m. ET by Brandon Galvin

Celtics fans are hoping for the best when it comes to Rajon Rondo's injured knee, but there is now fear that he may be suffering from a torn ACL, according to the Boston Herald's Mark Murphy. 

Rondo has a torn ACL.. per Doris Burke on ESPN

— Mike Petraglia (@Trags) January 27, 2013

The Boston Globe's Gary Washburn went on to describe any talk of a torn ACL as premature.

Celtics source says Rondo may have torn ACL - getting MRI for it now at New England Baptist.

— Mark Murphy (@Murf56) January 27, 2013

---End of update---

I hate to be the bearer of bad news, Boston fans, but you're going to be without Rajon Rondo, at least on Sunday. From A. Sherrod Blakely of CSN New England:

Source close to Rondo says guard is still waiting results of MRI and that ACL reports are premature #celtics

— gary washburn (@GwashNBAGlobe) January 27, 2013

#Celticstalk: #Celtics Rajon Rondo will not play due to a right hyperextended knee. Getting an MRI now. Status is day-to-day.

— A. Sherrod Blakely (@SherrodbCSN) January 27, 2013

Rondo had been one of the bright spots for the Celtics over the last two weeks and posted back-to-back triple-doubles against the New York Knicks (23 points, 11 assists, 10 rebounds) and Atlanta Hawks (16 points, 11 assists, 10 rebounds) on Thursday and Friday, respectively.

#Celticstalk: Rondo suffered the injury vs the #Hawks on Friday.

— A. Sherrod Blakely (@SherrodbCSN) January 27, 2013

Here's a fun fact for you: According to ESPN Stats and Information, Rondo has 15 triple-doubles since the start of last season, including the playoffs. LeBron James has the next-most in that span with three.

In his past five games, Rondo has averaged 18.8 points, 10.4 assists and 8.8 rebounds per game. You can point the finger of blame in a lot of directions given the Celtics' recent run of mediocrity, but you can't point one at Rondo.

For the season, he's averaging 13.7 points, 11.1 assists and 5.6 rebounds in 37.4 minutes per game.